Connect public, paid and private patent data with Google Patents Public Datasets

Adaptive air interface waveform

Download PDF

Info

Publication number
US20030203721A1
US20030203721A1 US10421168 US42116803A US2003203721A1 US 20030203721 A1 US20030203721 A1 US 20030203721A1 US 10421168 US10421168 US 10421168 US 42116803 A US42116803 A US 42116803A US 2003203721 A1 US2003203721 A1 US 2003203721A1
Authority
US
Grant status
Application
Patent type
Prior art keywords
waveform
frequency
carrier
sub
bandwidth
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
US10421168
Other versions
US6847678B2 (en )
Inventor
Roberto Berezdivin
Robert Breinig
Allan Topp
Scott Seidel
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Powerwave Cognition Inc
Original Assignee
Raytheon Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date

Links

Images

Classifications

    • HELECTRICITY
    • H03BASIC ELECTRONIC CIRCUITRY
    • H03MCODING; DECODING; CODE CONVERSION IN GENERAL
    • H03M13/00Coding, decoding or code conversion, for error detection or error correction; Coding theory basic assumptions; Coding bounds; Error probability evaluation methods; Channel models; Simulation or testing of codes
    • H03M13/25Error detection or forward error correction by signal space coding, i.e. adding redundancy in the signal constellation, e.g. Trellis Coded Modulation [TCM]
    • H03M13/255Error detection or forward error correction by signal space coding, i.e. adding redundancy in the signal constellation, e.g. Trellis Coded Modulation [TCM] with Low Density Parity Check [LDPC] codes
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00Arrangements for detecting or preventing errors in the information received
    • H04L1/0001Systems modifying transmission characteristics according to link quality, e.g. power backoff
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00Arrangements for detecting or preventing errors in the information received
    • H04L1/0001Systems modifying transmission characteristics according to link quality, e.g. power backoff
    • H04L1/0002Systems modifying transmission characteristics according to link quality, e.g. power backoff by adapting the transmission rate
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00Arrangements for detecting or preventing errors in the information received
    • H04L1/0001Systems modifying transmission characteristics according to link quality, e.g. power backoff
    • H04L1/0009Systems modifying transmission characteristics according to link quality, e.g. power backoff by adapting the channel coding
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00Arrangements affording multiple use of the transmission path
    • H04L5/003Arrangements for allocating sub-channels of the transmission path
    • H04L5/0044Arrangements for allocating sub-channels of the transmission path allocation of payload
    • H04L5/0046Determination of how many bits are transmitted on different sub-channels
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00Arrangements affording multiple use of the transmission path
    • H04L5/003Arrangements for allocating sub-channels of the transmission path
    • H04L5/0048Allocation of pilot signals, i.e. of signals known to the receiver
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00Arrangements affording multiple use of the transmission path
    • H04L5/003Arrangements for allocating sub-channels of the transmission path
    • H04L5/0058Allocation criteria
    • H04L5/006Quality of the received signal, e.g. BER, SNR, water filling
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00Arrangements affording multiple use of the transmission path
    • H04L5/003Arrangements for allocating sub-channels of the transmission path
    • H04L5/0058Allocation criteria
    • H04L5/0064Rate requirement of the data, e.g. scalable bandwidth, data priority
    • HELECTRICITY
    • H03BASIC ELECTRONIC CIRCUITRY
    • H03MCODING; DECODING; CODE CONVERSION IN GENERAL
    • H03M13/00Coding, decoding or code conversion, for error detection or error correction; Coding theory basic assumptions; Coding bounds; Error probability evaluation methods; Channel models; Simulation or testing of codes
    • H03M13/03Error detection or forward error correction by redundancy in data representation, i.e. code words containing more digits than the source words
    • H03M13/05Error detection or forward error correction by redundancy in data representation, i.e. code words containing more digits than the source words using block codes, i.e. a predetermined number of check bits joined to a predetermined number of information bits
    • H03M13/11Error detection or forward error correction by redundancy in data representation, i.e. code words containing more digits than the source words using block codes, i.e. a predetermined number of check bits joined to a predetermined number of information bits using multiple parity bits
    • H03M13/1102Codes on graphs and decoding on graphs, e.g. low-density parity check [LDPC] codes
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00Arrangements affording multiple use of the transmission path
    • H04L5/0001Arrangements for dividing the transmission path
    • H04L5/0014Three-dimensional division
    • H04L5/0016Time-frequency-code
    • H04L5/0021Time-frequency-code in which codes are applied as a frequency-domain sequences, e.g. MC-CDMA
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00Arrangements affording multiple use of the transmission path
    • H04L5/003Arrangements for allocating sub-channels of the transmission path
    • H04L5/0037Inter-user or inter-terminal allocation
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00Arrangements affording multiple use of the transmission path
    • H04L5/003Arrangements for allocating sub-channels of the transmission path
    • H04L5/0042Arrangements for allocating sub-channels of the transmission path intra-user or intra-terminal allocation

Abstract

In one embodiment, a method for generating an adaptive air interface waveform includes generating a waveform that includes a variable carrier frequency and variable bandwidth signal. The variable bandwidth signal includes one or more subcarriers that are dynamically placeable over a range of frequencies, and each subcarrier is separately modulated according to a direct sequence (DS) spread spectrum (SS) technique. The waveform has an embedded pilot usable to optimize one or more spectrum efficiencies of the waveform. A modulation constellation, a code rate, and a code length of the generated waveform are adapted according to an available spectrum and one or more sub-carrier conditions.

Description

    RELATED APPLICATION
  • [0001]
    This application claims the benefit, under 35 U.S.C. § 119(e), of U.S. Provisional Application No. 60/375,855, filed Apr. 25, 2002.
  • TECHNICAL FIELD OF THE INVENTION
  • [0002]
    This invention relates to wireless communication and more particularly to an adaptive air interface waveform.
  • BACKGROUND OF THE INVENTION
  • [0003]
    Current wireless communication systems do not adjust well to dynamic changes in the electromagnetic spectrum. As a result, these systems tend to provide a relatively low quality of service. As demand for high-bandwidth services increases, this problem will likely worsen.
  • [0004]
    Prior attempts to improve the ability of wireless communication systems to adjust to dynamic changes in the electromagnetic spectrum have focused on adaptation in a subset of dimensions available at a particular point in time. Data rates and processing gains have been modified to adapt specific waveforms, such as spread spectrum modulated signals, to a particular communication link condition. Various error-correction coding techniques with various parameters have been applied to a particular frequency assignment. Frequency adaptation techniques have been used in high frequency (HF) ranges. Frequency adaptation techniques have also been used in communication systems, such as wireless local area networks (WLANs), in which an open frequency is selected after a relatively slow seat for an open frequency.
  • [0005]
    Cellular communication systems typically operate at assigned channel frequencies. Slow assignments can use frequency division multiple access (FDMA) techniques. Adaptive modulation techniques have been investigated, but have been more or less limited to changing one or more parameters in a particular modulation scheme. Spectrum use can vary considerably throughout the world, which often necessitates a complex spectrum assignment process. Reallocation of bandwidth as a result of growth in commercial wireless markets could necessitate even more complex spectrum assignment processes in the future. In current wireless communication systems, one or more frequencies are statically assigned to a communication and sensor system (such as a radar system) without frequency overlap between the communication and sensor system and one or more other communication and sensor systems and with large spatial separation to prevent harmful interference between the communication and sensor system and one or more other communication and sensor systems.
  • SUMMARY OF THE INVENTION
  • [0006]
    Particular embodiments of the present invention may reduce or eliminate disadvantages and problems traditionally associated with wireless communication.
  • [0007]
    In one embodiment of the present invention, a method for generating an adaptive air interface waveform includes generating a waveform that includes a variable carrier frequency and variable bandwidth signal. The variable bandwidth signal includes one or more subcarriers that are dynamically placeable over a range of frequencies, and each subcarrier is separately modulated according to a direct sequence (DS) spread spectrum (SS) technique. The waveform has an embedded pilot usable to optimize one or more spectrum efficiencies of the waveform. A modulation constellation, a code rate, and a code length of the generated waveform are adapted according to an available spectrum and one or more sub-carrier conditions.
  • [0008]
    Particular embodiments of the present invention provide one or more advantages. In particular embodiments, dynamic adaptation in multiple parameters provides one or more performance options for wireless communication systems. In particular embodiments, the multiple parameters include adaptation in time, adaptation in power, variable bandwidth, variable data rate, variable modulation and coding, and spatial adaptation.
  • [0009]
    Particular embodiments provide a waveform that can adapt to an environment in multiple dimensions of available signal space. In particular embodiments, as an example, the signal space includes frequency, time, power, modulation, code, and spatial domain. Particular embodiments provide a waveform and a mechanism for selecting one or more parameters of the waveform and changing the waveform to adapt to one or more communication networks, one or more communication links, or one or more user requirements. Particular embodiments provide intelligent selection of multiple dimensions of an adaptation space, which can include frequency, modulation scheme and related parameters, coding scheme and related parameters, and data rates. Particular embodiments can provide a waveform optimized according to one or more link conditions. In particular embodiments, a modulation scheme can form multiple constellations and spatially adapt to transmission times. In particular embodiments, modulation uses a multi-carrier code division multiple access (MC-CDMA) CDMA) scheme according to which one or more individual carriers are independently modulated and coded according to the adaptation of the individual carriers to one or more communication links. In particular embodiments, adaptation to a communication link is more or less subject to one or more requirements associated with changes in data rates and frequency over time. In particular embodiments, one or more frequencies can be blocked or emphasized (effectively providing power control at each frequency), which can enable use of noncontiguous frequency sub-bands. In particular embodiments, a particular modulation and coding scheme is selected for a particular sub-band. In particular embodiments, a heteromorphic waveform can be morphed to one or more wireless communication resources (such as one or more frequency bands). In particular embodiments, frequency, modulation type and related parameter, coding type and related parameter, time, space, power, bandwidth, and processing are analyzed to provide relatively fast adaptation to time-varying channel conditions.
  • [0010]
    Particular embodiments provide an adaptable waveform for multiple wireless applications, such as applications for selecting multiple dimensions of an adaptation space and applications for estimating channel characteristics. In particular embodiments, power is controlled at frequencies in a waveform. In particular embodiments, noncontiguous frequency sub-bands are generated. In particular embodiments, a preferred channel organization is identified and selected. In particular embodiments, a preferred modulation and coding technique is selected according to one or more requirements associated with data rate and quality of service.
  • [0011]
    In particular embodiments, a spectrum-aware heteromorphic waveform that dynamically adapts to use available holes in a spectrum defined by frequency, space, and time enables shared use of common spectra. In particular embodiments, simultaneous adaptation of multiple waveform parameters enables more or less assured communication, while suppressing mutual harmful interference. Particular embodiments provide dynamic spectral assignment techniques that increase spectrum utilization by a factor of twenty.
  • [0012]
    Particular embodiments provide quick-response adaptive multi-carrier reorganization using one or more suitable available frequencies. Particular embodiments provide a signal design that includes a pilot for real-time sub-carrier channel estimation to more or less optimize waveform parameters and includes fast signal acquisition for transmission bursts. Particular embodiments provide one or more adaptive bandwidth-efficient code-modulation schemes with more or less simultaneous multi-dimensional variability with respect to multiple sub-carriers. Particular embodiments provide fast-reaction capability to quickly release channel usage and dynamically reconfigure hybrid multiple-access techniques.
  • [0013]
    Particular embodiments provide a single adaptable waveform that can work in multiple applications, such as WLAN applications and cellular applications. Particular embodiments provide a useful air interface that works in heterogeneous networks and can operate at data rates ranging from approximately 100 Mbps to 1 Gbps. A network environment could include a cellular macro environment, a micro-pico cellular environment, a WLAN or similar environment. A network environment could include one or more flexible architectures, such as cellular, centralized, ad hoc, and hybrid architectures. Particular embodiments support services and applications that have relatively high rates of data transmission. Particular embodiments automatically operate in gaps (or holes) in spectrum use. A hole can include multiple dimensions, such as time, frequency, and space.
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • [0014]
    To provide a more complete understanding of the present invention and the features and advantages thereof, reference is made to the following description, taken in conjunction with the accompanying drawings, in which:
  • [0015]
    [0015]FIG. 1 is a block diagram of a heteromorphic waveform function in accordance with the present invention within a next generation (XG) appliqué;
  • [0016]
    [0016]FIG. 2 is an illustration of a frequency agile heteromorphic waveform adapting to fill available time-frequency spectrum gaps;
  • [0017]
    [0017]FIG. 3 is an illustration of a heteromorphic waveform adapting to multiple variables to optimize spectral efficiency;
  • [0018]
    [0018]FIG. 4 is a multi-carrier organization, signaling and multi-level bandwidth-efficient coding and modulation for optimizing channel estimation data;
  • [0019]
    [0019]FIG. 5 is a representation of frequency/time/coding of a heteromorphic waveform in accordance with the present invention; and
  • [0020]
    [0020]FIG. 6 is a block diagram illustration of multi-level configuration of LDPC-based coded modulation scheme to facilitate rapid adaptation of code parameters.
  • DESCRIPTION OF EXEMPLARY EMBODIMENTS
  • [0021]
    The present invention is a heteromorphic waveform that dynamically adapts in frequency, time, modulation, code, data rate, power, signaling, and multi-carrier organization. The waveform will increase spectral efficiency by enabling efficient, opportunistic and cooperative spectrum use. It reacts to time-varying channel and use conditions by seizing time/frequency/spatial “holes” and using the most efficient coding, modulation, signaling and multi-carrier organization consistent with non-interfering communications. The heteromorphic waveform of the invention is subdivided into two major components as follows:
  • [0022]
    Adaptive Multi-Carrier Organization and Signaling configures a variable carrier frequency and variable bandwidth signal into one or many sub-carriers that are dynamically placed over a span of up to 250 MHz to avoid or minimize interference with transmissions of existing spectrum users. Each sub-carrier is independently modulated by direct sequence spread-spectrum (DS SS) for variable spreading and coding gain against cooperative, non-cooperative, and threat signals. A combination time/code pilot is embedded within the waveform to empower optimization based on sub-carrier channel estimates. The waveform supports a broad range of adaptive/hybrid multiple access schemes including combinations of CDMA, TDMA, FDMA, and FHMA.
  • [0023]
    Adaptive Multi-Level Bandwidth-Efficient Coding and Modulation (BECM) provides a family of BECM schemes, incorporating both multi-constellation modulation and forward error-correction coding. A Low Density Parity-Check Code (LDPC) coded modulation family will be used to advance the state-of-the-art in bandwidth efficiency and adaptation capability. Adapting the modulation constellation, code rate, and code length to match the available spectrum and sub-carrier conditions will maximize spectral efficiency while meeting quality of service (QoS) and data rate needs.
  • [0024]
    Overall spectral efficiency depends on a combination of frequency, space, and time efficiency of spectrum use. As these factors are closely inter-dependent, improving efficiency in one area often reduces efficiency in another.
  • [0025]
    Decrease spectral use per call/connection
  • [0026]
    increase modulation efficiency (bits/sec/Hz)
  • [0027]
    improve error-correction coding efficiency
  • [0028]
    compress source information
  • [0029]
    use adaptive (i.e., hybrid) multiple-access technique with “soft” capacity limits (e.g., MC-CDMA where FDMA/CDMA is possible.
  • [0030]
    Increase spatial reuse of bandwidth
  • [0031]
    increase power efficiency of modulation (minimum Eb/No to achieve sufficient BER)
  • [0032]
    use fast-adaptation in power control
  • [0033]
    reduce sensitivity to interference by waveform design
  • [0034]
    transmit a more “interference-friendly” waveform
  • [0035]
    spread signal information over wider bandwidth
  • [0036]
    increase directional sharing of bandwidth
  • [0037]
    Increase temporal sharing of bandwidth
  • [0038]
    coordinate time use of spectrum (e.g., via multiple access technique)
  • [0039]
    seize temporal “holes” in spectrum use as they become available (e.g., fast signal acquisition, burst-by-burst adaptation)
  • [0040]
    Many of these strategies conflict with each other—increasing the modulation efficiency decreases power efficiency. An accurate assessment of overall spectral utilization efficiency requires consideration of the complex interaction of frequency/time/space reuse of the electromagnetic spectrum.
  • [0041]
    Referring to FIG. 1, there is illustrated a heteromorphic waveform function that dynamically “morphs” to fill unused spectrum “holes” to dramatically increase spectral utilization. Overall waveform adaptation can be considered a hierarchical combination of “internal” and “external” functions, features, and parameter sets that determine the final transmitted waveform. The “external” set provides a definition of the frequency and temporal opportunities, along with other environment characteristics. The definition of the “internal” set modifies how the waveform “reacts” within its overall bandwidth span to implement strategies that optimize the waveform parameters for maximum spectrum efficiency consistent with local channel conditions, mutual interference avoidance, and LPI/LPD requirements.
  • [0042]
    The waveform of the present invention is a multi-carrier direct-sequence spread-spectrum (MC-DS SS), multi-rate, multi-constellation composite wideband waveform, quickly adaptable in time, frequency, power, modulation type, rate, code, multi-carrier organization and access method. An adaptable interface will allow a variety of access and control techniques and will adapt to other networks in the same frequency allocation band and physical space, and to time-varying channel conditions, threats and user needs. The waveform uses available short-duration (milliseconds) time segments on a packet basis, relinquishing channels to other networks as they become active, and seizing other channels based on predicted availability.
  • [0043]
    Frequency agility is achieved in several ways. First, the center frequency and RF bandwidth of the waveform can vary to occupy different frequency channels as the time usage of those channels varies. This is shown in FIG. 2, which is a representation of spectrum utilization for four frequency channels as a function of time. The existing users areas indicate transmissions from existing non-XG users and the empty spectrum areas indicate “holes” in time-frequency spectrum use. Consider an XG transmission as shown utilizing the first available “gap” on frequency channel F1. At point A, the waveform demonstrates macroscopic frequency agility by “morphing” its center frequency and bandwidth span to briefly occupy both frequency channels F1 and F2 before morphing again into channel F2. At point B, both the non-XG and XG transmissions occupy frequency channel F2. The non-XG transmissions occupy only a portion of frequency channel F2. Within the full bandwidth span of the XG transmission, the waveform organizes its sub-carriers to occupy some subset of the full span. Hence, the occupied bandwidth of the waveform will be less than or equal to the full bandwidth span. This microscopic frequency agility is used to avoid the portions of the frequency channel occupied by the non-XG signals. No power, or power within an acceptable SIR value for the non-XG signals, is transmitted on these unused sub-carriers in order to avoid interference with other transmissions. This combination of macroscopic and microscopic frequency agility maximizes XG spectral efficiency by seizing available gaps in frequency/space/time freeing up needed spectrum for both communications and sensor (such as radar) functions.
  • [0044]
    Referring to FIG. 3, there is shown a representation of the waveform in 2-D on the left and in 3-D on the right. The legend in the center of the figure highlights the areas of unspread QAM-based modulation, empty spectrum, excluded spectrum, and DS-SS-based modulation. The excluded spectrum represents the combination of time-frequency holes that are not available for waveform use as provided by externally controlled functions within the XG radio. The waveform demonstrates microscopic frequency agility and organizes the signal energy to avoid these exclusion zones, “morphing” dynamically to assume varied shapes in 3-D (frequency, time, power). Note that the exclusion zones are displayed as “blocked out” in the 3-D representation; no power is transmitted on those time-frequency combinations. On other sub-carriers, the waveform utilizes a combination of QAM-based modulation and both single carrier and multi-carrier direct-sequence spread spectrum coexisting in time on different frequency sub-channels, with time-varying modulation on a given sub-channel. Bandwidth-efficient coding and modulation (BECM) schemes and sub-carrier organization are also continuously adapted to maximize overall spectral utilization efficiency. Based on signal optimization and data rate requirements, the XG waveform may choose to leave some of the available time-frequency holes empty.
  • [0045]
    Construction of the waveform is partitioned into two major functional components as described below.
  • [0046]
    Adaptive Multi-Carrier Organization and Signaling configures a channel of up to 250 MHz bandwidth span into one or many variable width sub-carriers that are independently modulated by Direct-Sequence Spread Spectrum (DS-SS) for variable coding gain. The waveform will support a broad range of multiple access techniques including CDMA, TDMA, FDMA, FHMA, CSMA/CA, and RTS/CTS. Multiple users are served simultaneously and uniquely at varying data rates on sub-channels contained within the up to 250 MHz bandwidth span.
  • [0047]
    Adaptive Multi-Level Bandwidth-Efficient Coding and Modulation (BECM) provides a family of BECM schemes, incorporating both multi-constellation modulation and multi-level forward error correction coding that is optimized for sub-channel conditions. The baseline design uses Lower Density Parity-Check Codes (LDPC), currently favored by recent research in BECM, as the basis for coded modulation technology.
  • [0048]
    Adaptation in multiple dimensions is required in order to realize improvements in spectral efficiency by utilizing gaps in frequency/space/time. The heteromorphic waveform is simultaneously adaptive across many different dimensions as summarized in Table 1. The carrier frequency, bandwidth span, and occupied bandwidth are varied giving the XG transmission the required macroscopic frequency agility to “hop” from channel to channel as needed. The adaptive multi-carrier organization and signaling capability structures the up to 250 MHz bandwidth span into one or many variable width sub-carriers to support microscopic frequency agility and avoid transmissions within the waveform bandwidth. The resulting occupied bandwidth will depend on a combination of user data rate requirements, sub-channel conditions, and the processing capability of the XG platform. Adaptive multi-level bandwidth-efficient coding and modulation (BECM) takes advantage of XG channel estimation enabled by pilot symbol elements embedded within the waveform to select error-correction codes and modulation constellations that optimize capacity across the sub-channels. In addition to power control schemes used to minimize multiple access interference, the waveform has a burst-by-burst “fast-adapt” power control capability to rapidly relinquish use of an individual sub-carrier or the entire occupied bandwidth, as indicated by an external control signal in response to detection of non-XG signals coincident in time/frequency/space.
    TABLE
    The Heteromorphic Waveform simultaneously adapts in multiple
    dimensions to increase spectral utilization efficiency.
    Adaptation Capability Motivation Discussion
    Carrier Frequency Macroscopic Allows use of frequency
    Frequency Agility space/time “gaps: across
    full band of operation
    Bandwidth Span Macroscopic Allows use of different
    Frequency Agility width frequency/space/
    time “gaps”
    Sub-carrier Organization Microscopic Avoids interference and
    and Signaling Frequency Agility jammers
    (Occupied Bandwidth))
    Sub-carrier Bandwidth- Sub-channel Matches XG capacity to
    Efficient Coding and Optimized Data channel conditions
    Modulation (BECM) Rates
    Fast-Adapt Power Control Power Efficiency Promotes spatial reuse by
    reducing interference to
    other users
    Fast Acquisition/Pilot Rapid Allows use of short
    Symbols Seize/Release and frequency/space/time
    Channel “gaps”
    Estimation
  • [0049]
    Referring to FIG. 4, there is illustrated a waveform adaptation function residing in an XG radio. The adaptive multi-carrier organization and signaling section defines the preamble and pilot symbols, assigns sub-carrier placement and capacity, and applies any needed PN spreading, time diversity, and channelization to the user data. The adaptive multi-level bandwidth-efficient coding and modulation section codes and maps the coded data to the assigned sub-carriers. The signal is then adaptively power controlled resulting in the complete heteromorphic waveform bandwidth spanning up to 250 MHz. Channel estimation on the received data is performed by using the bi-directional pilot symbols embedded in the waveform for each transmission to estimate the widely varying sub-carrier channel characteristics between any pair of XG nodes. A decoded preamble contains channel estimate information from the other end of the link. Channel estimation data are passed to each adaptation block to optimize sub-carrier capacity. In this way, the channel estimates drive the adaptation of the multi-carrier organization and signaling and multi-level bandwidth-efficient coding and modulation. The pilot symbol design for channel estimation is discussed later.
  • [0050]
    The multi-carrier structure of the heteromorphic waveform allows spatial processing technology to be applied independently across the different sub-bands. Hence, the waveform will not only be compatible with current and future spatial processing, but will enable performance improvements compared with techniques that yield one solution for the full bandwidth. This includes both beam and null forming and space/path diversity processing systems, leveraging the enhanced interference suppression and higher data rate transmission gains achieved across multiple technology areas to increase spectral efficiency.
  • [0051]
    Referring to FIG. 5, there is illustrated multiple 3-D frequency/time/power representations of the waveform. The x-y plane in the far left picture shows a time-frequency mapping of the waveform. User data are mapped across up to K multiple variable-width sub-carriers. Multiple sub-carriers can be aggregated to form variable width sub-bands within the total RF bandwidth. An FFT-based implementation is utilized with variable length integration time. The power level of each sub-carrier as a function of frequency and time can be made arbitrarily small to avoid overlapping with other transmissions in the environment. The waveform simultaneously supports multiple spreading widths and modulation formats on different sub-carriers.
  • [0052]
    The top illustration in FIG. 5 shows a notional view of one way the waveform supports multiple users through CDMA. In the illustration, one sub-carrier is dedicated to a single user by assigning a single, shorter PN spreading code to that user to increase the data rate, while on the other sub-carrier, multiple variable rate users access the channel with different length PN codes. This is further shown in the illustration labeled “CDMA Mode” with the power of the codes of users CA, CB, and CC combining to form the aggregate power. Alternatively, one user can concentrate its data to occupy an entire sub-carrier using PSK/QAM-based modulation. The waveform also supports a hybrid mode where different portions of the user data are coded into different modulation formats as shown in the lower right comer of FIG. 5. Consider a non-XG transmission occupying the upper and lower portions of the frequency band.
  • [0053]
    Based on channel estimates provided by the waveform, the transmission shown is then mapped into two parts. Part 1 spreads the user data across the entire bandwidth in order to reduce the power spectral density below a level that is harmful to the non-XG transmission; part 2 concentrates the remaining data in the unoccupied bandwidth.
  • [0054]
    Across the bandwidth of a wideband signal, some frequencies will experience strong channel gains, while others experience deep fades. Both single carrier and MC-DS SS provides against narrowband interference and time-varying frequency-selective fading caused by the multipath propagation of the radio channel. For the single carrier case, when the bandwidth of a carrier exceeds the coherence bandwidth (BC) of the channel, multiple rake receiver “fingers” are needed to resolve the individual multipath components and capture the achievable diversity gain. The number of components that can be resolved, and hence, the number of rake receivers needed, is the ratio of the carrier bandwidth to the coherence bandwidth. An alternate approach is to divide the total bandwidth B into N multiple sub-carriers of narrower bandwidth b=B/N, each roughly equal to the coherence bandwidth (b≈BC). With multiple carriers, the frequency diversity of the original wide bandwidth is retained by diversity combining the multiple independent carriers in the frequency domain instead of the multiple rake fingers of the single carrier in the time domain. The amount of frequency diversity gain can be traded against data rate in this type of waveform design by transmitting a given data symbol across multiple sub-carriers (i.e., spread in frequency) and combining the test statistics from those sub-carriers before making a final decision on the data. In the limit, as each sub-carrier is modulated by data independent of the other sub-carriers, the overall transmission rate is maximized, and each symbol is sent without frequency diversity.
  • [0055]
    It has been shown that the performance of a single carrier DS SS waveform with a rake receiver and an equivalent designed MC-DS SS waveform are similar.
  • [0056]
    When the available bandwidth (and the data rate) is much greater than the coherence bandwidth, then a large number of rake fingers are needed, significantly increasing receiver complexity. Instead of N (=B/BC) fingers each processing a signal of bandwidth B for single carrier DS SS, the MC-DS SS waveform requires N fingers (one per sub-carrier) each processing a signal of bandwidth b (=B/N) resulting in a reduced complexity receiver. This occurs because the chip duration on the sub-carriers is M times longer than that of the single carrier system, reducing the number of computations needed to successfully demodulate the signal. When more than three to four rake fingers are needed, multi-carrier implementations are more efficient.
  • [0057]
    The implementation advantage of multi-carrier modulation is further highlighted when narrowband interferers are present since a multi-carrier system does not require a continuous frequency band. For application in XG systems, the multiple carriers are overlaid upon an existing set of narrowband signals simply by leaving appropriate gaps in the placement of the multiple sub-carriers. This adaptive “re-routing” of sub-carrier placement to avoid the interferers can be accomplished without performance loss relative to contiguous sub-carriers with the same total occupied bandwidth. A single-carrier signal must implement adaptive notch filters whose achievable notch depth and notch bandwidth are related in complexity.
  • [0058]
    An advantage of MC-DS SS waveform flexibility is using different data rates in some or all of the sub-carriers in order to send more data on “strong” sub-carriers while sending less data on “weak” ones. The ability to capitalize on this flexibility depends upon how accurately the system estimates the state of the fade on the different sub-carriers. The pilot performs this channel estimation where the ability to accurately estimate the fade depends upon many system parameters including signal-to-noise ratio (SNR), signal-to-interference ratio (SIR), Doppler spread, and forward error correction.
  • [0059]
    The waveform of the invention incorporates a channel estimation capability to guide adaptation of multi-carrier organization and signaling and bandwidth-efficient coding and modulation on a sub-carrier basis to optimize spectral utilization efficiency. The basis for channel estimation is a hybrid CDMA/TDMA pilot that consists of a spreading code embedded within the preamble of a data burst. These pilot symbols are logically equivalent to a training sequence for an adaptive equalizer. Use of a pilot allows coherent demodulation, improving power efficiency. Spreading the pilot reduces the probability of detection and intercept. Anti-jam resistance is provided by making sure that the pilot is spread at least as much as the data so that a jammer could not easily defeat the waveform by focusing efforts solely on the pilot.
  • [0060]
    The use of a pilot also provides a “snapshot” of sub-carrier fading that can be used to estimate the coherence bandwidth of the channel. This estimate is used as the basis for adapting sub-carrier width and placement subject to spectrum gap availability constraints. Just as sub-carrier width is driven by the coherence bandwidth of the channel, the rate of change of the fading is driven by the coherence time of the channel. The coherence time provides a measure of how long the channel estimates remain valid, and is inversely proportional to Doppler shift. For example, a vehicle moving at 50 mph and communicating on a frequency of 2.5 GHz has a Doppler shift of 186 Hz, indicating that channel estimates and subsequent multivariate adaptation will need to be updated on the order of every 5.4 ms. Data will be sent at the same rate on each sub-carrier when channel estimates are either not available, or whose ages have exceeded the coherence time of the channel.
  • [0061]
    Using the MC signal as the basis for multi-carrier organization and signaling gives a wide array of design trade-offs to maximize spectral efficiency. Multiple combinations of different waveform parameters provide an equivalent user payload data rate. The effectiveness of adaptation in multiple variables includes the following:
  • [0062]
    Variable bandwidth: varying the bandwidth span and occupied bandwidth allows the waveform to match the bandwidth available. Wider bandwidths provide a greater amount of raw capacity that can be traded for diversity, coding, spreading gain, etc. Narrower bandwidths provide a structure that allows waveform operation when small amounts of spectrum are available.
  • [0063]
    Variable number of sub-carriers: by varying the number of sub-carriers, the available bandwidth can be organized to avoid narrowband interference/jamming on select sub-carriers. If just one sub-carrier is used, the waveform “morphs” into a single carrier waveform (e.g., DS SS, conventional QPSK, etc.).
  • [0064]
    Variable sub-carrier organization: mapping user data into different combinations of sub-carriers allows different types of system gain to be applied to the signal to combat fading and interference. Spreading gain and frequency diversity gain can be applied across adjacent sub-carriers, and varying amounts of interference averaging can be achieved by mapping the data across non-contiguous sub-carriers.
  • [0065]
    Variable sub-carrier data rate: by monitoring the state of each sub-carrier, and using higher order modulation where channel conditions allow, the data rate within each sub-carrier can be optimized.
  • [0066]
    Variable frequency diversity: by transmitting multiple bits in parallel on different sub-carriers (multi-carrier load sharing), data rate is traded for frequency diversity.
  • [0067]
    Because of the severe sensitivity of any DS SS system to the near-far problem, one or more means of mitigation must be part of the system design. For ad-hoc wireless systems, the commercial cellular CDMA solution of base-station-oriented power control requires centralized control of all the transmitters. Alternatives to enhancing the waveform to near-far interference includes the following:
  • [0068]
    The XG capability of “morphing” the signal in frequency/space/time itself provides some inherent resistance to near-far interference. Adaptation strategies for multi-carrier organization and signaling and bandwidth-efficient coding and modulation consider the effects of near-far multiple access interference (MAI).
  • [0069]
    To seize and release spectrum opportunities, the data are organized into variable-length packets. This leads naturally into the ability to multiplex users based on packet arrival time. Hence, TDMA can be supported by the waveform for ad-hoc mobile networking.
  • [0070]
    Sub-carrier slots can be arranged to support FHMA with a near-orthogonal frequency-hopping (FH) pattern so that near-far signals typically occupy different sub-carriers at any instant in time.
  • [0071]
    Within the ad-hoc network, clusters of users arrange themselves in sub-networks, improving the effectiveness of standard power control.
  • [0072]
    When LPI is not required, a single-user MAI suppression technique based upon a receiver designed to minimize mean-square error can be employed. Such a receiver is well-suited for an ad-hoc network, since it does not require apriori knowledge of the parameters of any of the users in the system. However, short spreading sequences (i.e., those whose period equals the duration of a data symbol) are used.
  • [0073]
    When available, spatial processing provides additional near-far resistance with appropriate beamforming. In particular, sub-band beamforming is anticipated to provide greater amounts of near-far interference suppression.
  • [0074]
    The heteromorphic waveform described herein allows solution of the near-far problem through a combination of several techniques of adaptive frequency and/or time allocation, frequency hopping, power control or spatial arrays. Thus, the waveform will be compatible with TDMA, TSMA, FDMA, CDMA, FHMA and other commonly used supplemental control techniques such as CSMA/CA and RTS/CTS. For integration as an appliqué solution, the waveform utilizes the multiple access scheme of the base radio system if necessary, or adapt it if allowed. Hybrid multiple access schemes can be used that dynamically match the multiple access format to the local spectrum utilization characteristics leading to even further increases in spectrum utilization.
  • [0075]
    Error-correction codes are well known to provide significantly increased power efficiency for a small (or no) reduction in bandwidth efficiency at the expense of increased complexity. The baseline error-correction coding and modulation design is based on an adaptive low-density parity-check coded (LDPC) modulation code family that is well-suited for use in XG systems.
  • [0076]
    LDPC codes are linear binary block codes whose parity-check matrix H possesses a low density of ones (i.e., it consists mostly of zeros). These characteristics endow the codes with an improved weight spectrum and a simple near-optimum decoding algorithm. The decoding algorithm is iterative, much like the trellis-turbo decoding algorithm, but the LDPC algorithm iterates over a graph rather than between two trellises. Note that although for TTCM the two trellises can be put in graph form, the graph is much more complex than the LDPC graph. The described LDPC modulation family enables fast adaptation by the following techniques:
  • [0077]
    The use of a multi-level encoding structure, which is a natural architecture for multi-rate coding
  • [0078]
    Simple component encoder implementation via simple shift-register circuits through the use of cyclic and quasi-cyclic LDPC codes
  • [0079]
    The heteromorphic waveform of the present invention will incorporate a range of code lengths and code rates to optimize performance based on spectrum availability and sub-carrier channel conditions.
  • [0080]
    Referring to FIG. 6, there is illustrated binary LDPC codes arranged in a multi-level configuration, consisting of N component codes and a mapper (modulator). By this approach, the bandwidth efficiency (and bandwidth) can be widely varied by varying the code rates of the component codes and/or the constellation size of the mapper. This multi-level configuration gives near-capacity performance. The number of levels is generally matched to the constellation size. For a 2N-ary constellation, there will be N encoders.
  • [0081]
    Encoders for cyclic LDPC codes can be constructed using the well-known shift-register circuits used to encode BCH codes. The nominal codeword length is n and the nominal data word length is k giving a nominal code rate of k/n with these parameters easily modified. Low-latency adaptation will need a range of code lengths.
  • [0082]
    Using LDPC code families as the basis for bandwidth-efficient coding and modulation gives a wide array of trade-offs to maximize spectral efficiency. Multiple combinations of modulation constellation and code rate provide an equivalent user payload data rate, and code length will also impact error performance. The effectiveness of adaptation in multiple variables includes the following:
  • [0083]
    Modulation constellation: varying the modulation constellation provides the capability to trade-off raw data (rate for power efficiency. Small modulation constellations allow operation at lower receive power levels to extend coverage range. Larger modulation constellations (up to 64 QAM) give larger raw capacity that can then be traded for coding gain to match sub-carrier channel conditions.
  • [0084]
    Code rate: varying code rate provides an additional degree of freedom to match code strength to local channel conditions. Low rate codes help extend link margin and high rate codes will deliver an appropriate amount of coding gain while maximizing user data rate.
  • [0085]
    Code length: variable code lengths are needed to efficiently map user data into a wide range of sub-carrier capacities. Long codes will be used to operate near the capacity limit when long temporal “gaps” in spectrum are available. Short codes will be used to meet low latency requirements, provide fast adaptation, and allow the waveform to seize short/small spectrum gaps.
  • [0086]
    Multi-level coding: using multi-level coding simplifies the coding and decoding architecture and is a natural fit for supporting adaptive coding strategies by “pre-filling” multiple user data blocks so that it is ready for immediate transmission once channel estimation data are available to guide code selection.
  • [0087]
    The combination of a wideband MC-DS SS waveform structure that can dynamically change carrier frequency, bandwidth, and sub-carrier organization and signaling with bandwidth-efficient coding and modulation is used to create a heteromorphic waveform. Waveform architecture has been structured to innovate beyond the current state-of-the-art in wireless communications and information theory research. This invention extends the boundaries by adapting to fill available spectrum “holes” and optimizing user data rate on available sub-carriers using simultaneous multivariate adaptation of waveform parameters.
  • [0088]
    Although a preferred embodiment of the invention has been illustrated in the accompanying drawings and described in the foregoing description, it will be understood that the invention is not limited to the embodiments disclosed, but is capable of numerous rearrangements and modifications of parts and elements without departing from the spirit of the invention.

Claims (31)

What is claimed is:
1. A system for generating an adaptive air interface waveform, the system comprising:
an adaptive multi-carrier organization and signaling component operable to generate a waveform comprising a variable carrier frequency and variable bandwidth signal that comprises one or more subcarriers that are dynamically placeable over a range of frequencies, each subcarrier being separately modulated according to a direct sequence (DS) spread spectrum (SS) technique, the waveform having an embedded pilot usable to optimize one or more spectrum efficiencies of the waveform; and
an adaptive multi-level bandwidth-efficient coding and modulation (BECM) component operable to adapt a modulation constellation, a code rate, and a code length of the generated waveform according to an available spectrum and one or more sub-carrier conditions.
2. The system of claim 1, wherein the generated waveform is a heteromorphic waveform operable to dynamically adapt with respect to one or more of frequency, time, modulation, code, data rate, power, signaling, and multi-carrier organization.
3. The system of claim 1, wherein the range of frequencies spans approximately 250 MHz.
4. The system of claim 1, wherein the generated waveform is operable to use one or more unused holes in a spectrum defined by one or more of frequency, space, and time.
5. The system of claim 1, wherein the generated waveform supports a plurality of multiple access (MA) techniques.
6. The system of claim 5, wherein the plurality of MA techniques comprise:
one or more carrier division multiple access (CDMA) techniques;
one or more time division multiple access (TDMA) techniques;
one or more frequency division multiple access (FDMA) techniques;
one or more frequency-hopped multiple access (FHMA) techniques;
7. The system of claim 5, wherein at least one of the MA techniques is a hybrid MA technique.
8. The system of claim 1, wherein the BECM uses a low-density parity-check (LDPC) code module technique to adapt a modulation constellation, a code rate, and a code length of the generated waveform.
9. The system of claim 1, wherein the BECM is operable to adapt a modulation constellation, a code rate, and a code length of the generated waveform according to one or more quality of service (QoS) requirements and one or more data rate requirements, in addition to an available spectrum and one or more sub-carrier conditions.
10. The system of claim 1, wherein the generated waveform exhibits both macroscopic frequency agility and microscopic frequency agility.
11. A method for generating an adaptive air interface waveform, the method comprising:
generating a waveform comprising a variable carrier frequency and variable bandwidth signal that comprises one or more subcarriers that are dynamically placeable over a range of frequencies, each subcarrier being separately modulated according to a direct sequence (DS) spread spectrum (SS) technique, the waveform having an embedded pilot usable to optimize one or more spectrum efficiencies of the waveform; and
adapting a modulation constellation, a code rate, and a code length of the generated waveform according to an available spectrum and one or more sub-carrier conditions.
12. The method of claim 11, wherein the generated waveform is a heteromorphic waveform operable to dynamically adapt with respect to one or more of frequency, time, modulation, code, data rate, power, signaling, and multi-carrier organization.
13. The method of claim 11, wherein the range of frequencies spans approximately 250 MHz.
14. The method of claim 11, wherein the generated waveform is operable to use one or more unused holes in a spectrum defined by one or more of frequency, space, and time.
15. The method of claim 11, wherein the generated waveform supports a plurality of multiple access (MA) techniques.
16. The method of claim 15, wherein the plurality of MA techniques comprise:
one or more carrier division multiple access (CDMA) techniques;
one or more time division multiple access (TDMA) techniques;
one or more frequency division multiple access (FDMA) techniques;
one or more frequency-hopped multiple access (FHMA) techniques;
17. The method of claim 15, wherein at least one of the MA techniques is a hybrid MA technique.
18. The method of claim 11, wherein a low-density parity-check (LDPC) code module technique is used to adapt a modulation constellation, a code rate, and a code length of the generated waveform.
19. The method of claim 11, wherein the modulation constellation, code rate, and code length of the generated waveform is adapted according to one or more quality of service (QoS) requirements and one or more data rate requirements, in addition to an available spectrum and one or more sub-carrier conditions.
20. The method of claim 11, wherein the generated waveform exhibits both macroscopic frequency agility and microscopic frequency agility.
21. Software for generating an adaptive air interface waveform, the software embodied in media and when executed operable to:
generate a waveform comprising a variable carrier frequency and variable bandwidth signal that comprises one or more subcarriers that are dynamically placeable over a range of frequencies, each subcarrier being separately modulated according to a direct sequence (DS) spread spectrum (SS) technique, the waveform having an embedded pilot usable to optimize one or more spectrum efficiencies of the waveform; and
adapt a modulation constellation, a code rate, and a code length of the generated waveform according to an available spectrum and one or more sub-carrier conditions.
22. The software of claim 21, wherein the generated waveform is a heteromorphic waveform operable to dynamically adapt with respect to one or more of frequency, time, modulation, code, data rate, power, signaling, and multi-carrier organization.
23. The software of claim 21, wherein the range of frequencies spans approximately 250 MHz.
24. The software of claim 21, wherein the generated waveform is operable to use one or more unused holes in a spectrum defined by one or more of frequency, space, and time.
25. The software of claim 21, wherein the generated waveform supports a plurality of multiple access (MA) techniques.
26. The software of claim 25, wherein the plurality of MA techniques comprise:
one or more carrier division multiple access (CDMA) techniques;
one or more time division multiple access (TDMA) techniques;
one or more frequency division multiple access (FDMA) techniques;
one or more frequency-hopped multiple access (FHMA) techniques;
27. The software of claim 25, wherein at least one of the MA techniques is a hybrid MA technique.
28. The software of claim 21, wherein a low-density parity-check (LDPC) code module technique is used to adapt a modulation constellation, a code rate, and a code length of the generated waveform.
29. The software of claim 21, wherein the modulation constellation, code rate, and code length of the generated waveform is adapted according to one or more quality of service (QoS) requirements and one or more data rate requirements, in addition to an available spectrum and one or more sub-carrier conditions.
30. The software of claim 21, wherein the generated waveform exhibits both macroscopic frequency agility and microscopic frequency agility.
31. A system for generating an adaptive air interface waveform, the system comprising:
means for generating a waveform comprising a variable carrier frequency and variable bandwidth signal that comprises one or more subcarriers that are dynamically placeable over a range of frequencies, each subcarrier being separately modulated according to a direct sequence (DS) spread spectrum (SS) technique, the waveform having an embedded pilot usable to optimize one or more spectrum efficiencies of the waveform; and
means for adapting a modulation constellation, a code rate, and a code length of the generated waveform according to an available spectrum and one or more sub-carrier conditions.
US10421168 2002-04-25 2003-04-22 Adaptive air interface waveform Active US6847678B2 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US37585502 true 2002-04-25 2002-04-25
US10421168 US6847678B2 (en) 2002-04-25 2003-04-22 Adaptive air interface waveform

Applications Claiming Priority (9)

Application Number Priority Date Filing Date Title
US10421168 US6847678B2 (en) 2002-04-25 2003-04-22 Adaptive air interface waveform
KR20047017111A KR100934302B1 (en) 2002-04-25 2003-04-24 The adaptive air interface waveform
JP2004500445A JP2006515119A (en) 2002-04-25 2003-04-24 Generating a waveform of the adaptive air interface
PCT/US2003/013065 WO2003092212A1 (en) 2002-04-25 2003-04-24 An adaptive air interface waveform
CA 2480847 CA2480847C (en) 2002-04-25 2003-04-24 An adaptive air interface waveform
RU2004134568A RU2339170C2 (en) 2002-04-25 2003-04-24 Adaptive waveform of radio interface signal
EP20030724276 EP1497942A1 (en) 2002-04-25 2003-04-24 An adaptive air interface waveform
EP20100165122 EP2219315A1 (en) 2002-04-25 2003-04-24 An adaptive air interface waveform
CN 03815063 CN1666453A (en) 2002-04-25 2003-04-24 Adaptive air interface waveform

Publications (2)

Publication Number Publication Date
US20030203721A1 true true US20030203721A1 (en) 2003-10-30
US6847678B2 US6847678B2 (en) 2005-01-25

Family

ID=29254620

Family Applications (1)

Application Number Title Priority Date Filing Date
US10421168 Active US6847678B2 (en) 2002-04-25 2003-04-22 Adaptive air interface waveform

Country Status (8)

Country Link
US (1) US6847678B2 (en)
JP (1) JP2006515119A (en)
KR (1) KR100934302B1 (en)
CN (1) CN1666453A (en)
CA (1) CA2480847C (en)
EP (2) EP1497942A1 (en)
RU (1) RU2339170C2 (en)
WO (1) WO2003092212A1 (en)

Cited By (60)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20040054960A1 (en) * 2002-07-03 2004-03-18 Mustafa Eroz Method and system for providing low density parity check (LDPC) encoding
US20050030887A1 (en) * 2003-08-06 2005-02-10 Jacobsen Eric A. Technique to select transmission parameters
US20050063484A1 (en) * 2002-07-26 2005-03-24 Mustafa Eroz Satellite communincation system utilizing low density parity check codes
US20050079840A1 (en) * 2003-10-11 2005-04-14 Visteon Global Technologies, Inc. Method for controlling the selectivity of a tuner in a variable bandwidth system
US20050085223A1 (en) * 2003-10-20 2005-04-21 Accton Technology Corporation System and method for multi-path simulation
EP1553706A1 (en) * 2004-01-10 2005-07-13 Broadcom Corporation Bandwidth efficient LDPC (low density parity check) coded modulation scheme based on MLC (multi-level code) signals
US20050271160A1 (en) * 2002-07-03 2005-12-08 Mustafa Eroz Bit labeling for amplitude phase shift constellation used with low density parity check (LDPC) codes
EP1615367A1 (en) * 2004-07-10 2006-01-11 Samsung Electronics Co., Ltd. Method of allocating subcarriers on the downlink of a CDMA system
WO2006019441A1 (en) * 2004-07-19 2006-02-23 Telefonaktiebolaget Lm Ericsson (Publ) Selective multicarrier cdma network
US20060083325A1 (en) * 2004-09-30 2006-04-20 Infineon Technologies Ag Method and receiver circuit for reducing RFI interference
US20060092902A1 (en) * 2004-11-01 2006-05-04 General Instrument Corporation Methods, apparatus and systems for terrestrial wireless broadcast of digital data to stationary receivers
US20060116078A1 (en) * 2002-12-24 2006-06-01 Matsushita Electric Industrial Co., Ltd. Radio communication apparatus and radio transmission method
US20060131379A1 (en) * 2004-12-21 2006-06-22 Junichi Aoki Physical distribution management system and method for customized products
US20060164292A1 (en) * 2002-12-03 2006-07-27 Josef Buechler Radar system comprising integrated data transmission
US20060205356A1 (en) * 2005-03-09 2006-09-14 Rajiv Laroia Methods and apparatus for antenna control in a wireless terminal
US20060205355A1 (en) * 2005-03-09 2006-09-14 Rajiv Laroia Methods and apparatus for transmitting signals facilitating antenna control
US20060203709A1 (en) * 2005-03-09 2006-09-14 Rajiv Laroia Methods and apparatus for implementing, using, transmitting, and/or receiving signals at least some of which include intentional null tones
EP1745571A2 (en) * 2004-05-01 2007-01-24 Waltical Solutions, Inc. Methods and apparatus for multi-carrier communications with variable channel bandwidth
US20070076666A1 (en) * 2005-10-03 2007-04-05 Riveiro Juan C Multi-Wideband Communications over Power Lines
US20070075843A1 (en) * 2005-10-03 2007-04-05 Riveiro Juan C Multi-Wideband Communications over Power Lines
EP1783942A1 (en) * 2005-11-08 2007-05-09 Motorola, Inc. Low-density parity check coding for orthogonal frequency division multiplex systems
US20070118030A1 (en) * 2005-11-22 2007-05-24 Isense Corporation Method and apparatus for analyte data telemetry
US20070229231A1 (en) * 2005-10-03 2007-10-04 Hurwitz Jonathan E D Multi-Wideband Communications over Multiple Mediums within a Network
US20080008081A1 (en) * 2006-07-06 2008-01-10 Gigle Semiconductor Inc. Adaptative multi-carrier code division multiple access
US20080039129A1 (en) * 2004-06-30 2008-02-14 Xiaodong Li Methods and Apparatus for Power Control in Multi-carier Wireless Systems
US20080082895A1 (en) * 2002-07-26 2008-04-03 The Directv Group, Inc. Method and system for generating low density parity check codes
US20080089398A1 (en) * 2006-10-12 2008-04-17 Cormier Daniel R Determining a mode to transmit data
US20080112427A1 (en) * 2006-11-10 2008-05-15 Seidel Scott Y Autonomous dynamic spectrum access
US20080112428A1 (en) * 2006-11-10 2008-05-15 Seidel Scott Y Scheduling for autonomous dynamic spectrum access systems
US20080112341A1 (en) * 2006-11-10 2008-05-15 Seidel Scott Y Method and system for using selected bearer channels
US20080113624A1 (en) * 2006-11-10 2008-05-15 Seidel Scott Y Method and apparatus for adjusting waveform parameters for an adaptive air interface waveform
US20080113667A1 (en) * 2006-11-10 2008-05-15 Seidel Scott Y Bearer selection and negotiation in autonomous dynamic spectrum access systems
US20080112426A1 (en) * 2006-11-10 2008-05-15 Seidel Scott Y Adaptive control channel initialization operations for autonomous dynamic spectrum access systems
US20080117896A1 (en) * 2006-11-21 2008-05-22 Veronica Romero Network repeater
US7383487B2 (en) 2004-01-10 2008-06-03 Broadcom Corporation IPHD (iterative parallel hybrid decoding) of various MLC (multi-level code) signals
US20080130640A1 (en) * 2005-10-03 2008-06-05 Jonathan Ephraim David Hurwitz Multi-Wideband Communications over Multiple Mediums
US7398455B2 (en) 2002-07-03 2008-07-08 The Directv Group, Inc. Method and system for decoding low density parity check (LDPC) codes
US20080212549A1 (en) * 2007-01-30 2008-09-04 Samsung Electronics Co., Ltd. Apparatus and method for receiving signal in a communication system
US20080254749A1 (en) * 2007-04-13 2008-10-16 Provigent Ltd. Management of variable-rate communication links
US20080260084A1 (en) * 2007-04-20 2008-10-23 Kabushiki Kaisha Toshiba Radio communication apparatus and system
US20080260073A1 (en) * 2006-07-14 2008-10-23 Hui Jin Ecoding and decoding methods and apparatus for use in a wireless communication system
US20090147869A1 (en) * 2005-08-22 2009-06-11 Matsushita Electric Industrial Co., Ltd. Communication terminal apparatus, base station apparatus and reception quality reporting method
US20100052899A1 (en) * 2008-08-28 2010-03-04 Isense Corporation Method and system for communication between wireless devices
US20100117734A1 (en) * 2008-10-13 2010-05-13 Jonathan Ephraim David Hurwitz Programmable Gain Amplifier and Transconductance Compensation System
US7795973B2 (en) 2008-10-13 2010-09-14 Gigle Networks Ltd. Programmable gain amplifier
US7796708B2 (en) 2006-03-29 2010-09-14 Provigent Ltd. Adaptive receiver loops with weighted decision-directed error
US20100265992A1 (en) * 2006-07-06 2010-10-21 Jose Abad Molina Adaptative Multi-Carrier Code Division Multiple Access
US7821938B2 (en) 2007-04-20 2010-10-26 Provigent Ltd. Adaptive coding and modulation for synchronous connections
US7839952B2 (en) 2006-12-05 2010-11-23 Provigent Ltd Data rate coordination in protected variable-rate links
US20110003609A1 (en) * 2009-07-01 2011-01-06 Sundstroem Lars Power Efficient Data Transmission
US8001445B2 (en) 2007-08-13 2011-08-16 Provigent Ltd. Protected communication link with improved protection indication
US8040985B2 (en) 2007-10-09 2011-10-18 Provigent Ltd Decoding of forward error correction codes in the presence of phase noise
US20130115967A1 (en) * 2011-11-07 2013-05-09 Qualcomm Incorporated Adaptive flexible bandwidth wireless systems
US8483154B2 (en) 2008-02-06 2013-07-09 Nec Corporation Subcarrier allocation method and apparatus thereof
US20140098782A1 (en) * 2012-10-05 2014-04-10 Sierra Wireless. Inc. Enhancement for lte communication systems
US8885814B2 (en) 2006-07-25 2014-11-11 Broadcom Europe Limited Feedback impedance control for driving a signal
US20150349987A1 (en) * 2014-05-29 2015-12-03 Qualcomm Incorporated Asynchronous multicarrier communications
US9220101B2 (en) 2011-11-07 2015-12-22 Qualcomm Incorporated Signaling and traffic carrier splitting for wireless communications systems
US9516531B2 (en) 2011-11-07 2016-12-06 Qualcomm Incorporated Assistance information for flexible bandwidth carrier mobility methods, systems, and devices
US9848339B2 (en) 2011-11-07 2017-12-19 Qualcomm Incorporated Voice service solutions for flexible bandwidth systems

Families Citing this family (57)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7146176B2 (en) 2000-06-13 2006-12-05 Shared Spectrum Company System and method for reuse of communications spectrum for fixed and mobile applications with efficient method to mitigate interference
US7385915B2 (en) 2002-07-31 2008-06-10 Nokia Corporation Apparatus, and associated method, for facilitating communication allocation in a radio communication system
US20060013181A1 (en) * 2002-07-31 2006-01-19 Victor Stolpman Apparatus, and associated method, for allocating communications in a multi-channel communication system
US7362794B2 (en) * 2002-09-17 2008-04-22 Sony Corporation Channel equalisation
US7529265B1 (en) * 2002-12-03 2009-05-05 Rockwell Collins, Inc. Frequency self-organizing radio network system and method
US8099099B2 (en) * 2003-02-19 2012-01-17 Qualcomm Incorporated Methods and apparatus related to assignment in a wireless communications system
US7409010B2 (en) * 2003-06-10 2008-08-05 Shared Spectrum Company Method and system for transmitting signals with reduced spurious emissions
US7085290B2 (en) * 2003-09-09 2006-08-01 Harris Corporation Mobile ad hoc network (MANET) providing connectivity enhancement features and related methods
US7394826B2 (en) * 2003-09-09 2008-07-01 Harris Corporation Mobile ad hoc network (MANET) providing quality-of-service (QoS) based unicast and multicast features
US7245674B2 (en) * 2003-11-28 2007-07-17 Texas Instruments Incorporated Method and system for providing low power WLAN receiver
US7489621B2 (en) * 2003-12-30 2009-02-10 Alexander A Maltsev Adaptive puncturing technique for multicarrier systems
CN102064848B (en) * 2004-01-29 2012-07-25 桥扬科技有限公司 Method and apparatus for movable station and base station in a multi-subzones broadband wireless system
EP1712089B1 (en) 2004-01-29 2014-11-19 Neocific, Inc. Methods and apparatus for multi-carrier, multi-cell wireless communication networks
CN1943152B (en) 2004-02-13 2011-07-27 桥扬科技有限公司 Methods and apparatus for multi-carrier communication systems with adaptive transmission and feedback
US7161988B2 (en) * 2004-04-12 2007-01-09 The Directv Group, Inc. Method and apparatus for minimizing co-channel interference
US7412209B2 (en) * 2004-04-12 2008-08-12 The Directv Group, Inc. Shifted channel characteristics for mitigating co-channel interference
DE602004012069T2 (en) * 2004-05-03 2009-02-26 Alcatel Lucent Transmission mode selection by means of a composite signal quality estimate
US7672285B2 (en) 2004-06-28 2010-03-02 Dtvg Licensing, Inc. Method and apparatus for minimizing co-channel interference by scrambling
US7263335B2 (en) 2004-07-19 2007-08-28 Purewave Networks, Inc. Multi-connection, non-simultaneous frequency diversity in radio communication systems
US7453856B2 (en) * 2004-09-03 2008-11-18 Telefonaktiebolaget Lm Ericsson (Publ) Method, apparatus, and communications interface for sending and receiving data blocks associated with different multiple access techniques
WO2006050181A3 (en) 2004-10-29 2006-08-10 Univ Ohio Spectrally shaped generalized multitone direct sequence spread spectrum modulation
JP4476324B2 (en) * 2005-03-02 2010-06-09 富士通株式会社 Ofdm communication system and ofdm communication method
US20070297386A1 (en) * 2005-07-28 2007-12-27 Interdigital Technology Corporation Method and system for scheduling uplink transmissions in a single carrier frequency division multiple access system
US8331216B2 (en) * 2005-08-09 2012-12-11 Qualcomm Incorporated Channel and interference estimation in single-carrier and multi-carrier frequency division multiple access systems
WO2007025121A1 (en) 2005-08-26 2007-03-01 The Directv Group, Inc. Method and apparatus for determining scrambling codes for signal transmission
US9705562B2 (en) 2006-07-25 2017-07-11 Broadcom Europe Limited Dual transformer communication interface
US8125961B2 (en) * 2005-10-25 2012-02-28 Qualcomm Incorporated Four way handshake for robust channel estimation and rate prediction
US7661037B2 (en) * 2005-10-27 2010-02-09 Samsung Electronics Co., Ltd. LDPC concatenation rules for IEEE 802.11n systems
US7707479B2 (en) * 2005-12-13 2010-04-27 Samsung Electronics Co., Ltd. Method of generating structured irregular low density parity checkcodes for wireless systems
US7620880B2 (en) * 2005-12-20 2009-11-17 Samsung Electronics Co., Ltd. LDPC concatenation rules for IEEE 802.11n system with packets length specified in OFDM symbols
US7584406B2 (en) 2005-12-20 2009-09-01 Samsung Electronics Co., Ltd. LDPC concatenation rules for IEEE 802.11n system with packets length specific in octets
US20070180349A1 (en) * 2006-01-31 2007-08-02 Jacobsen Eric A Techniques for uequal error protection for layered protection applications
US8155649B2 (en) 2006-05-12 2012-04-10 Shared Spectrum Company Method and system for classifying communication signals in a dynamic spectrum access system
US8326313B2 (en) * 2006-05-12 2012-12-04 Shared Spectrum Company Method and system for dynamic spectrum access using detection periods
US20070265016A1 (en) * 2006-05-12 2007-11-15 Nokia Corporation Apparatus, method and computer program product providing partitioned downlink shared control channel having fixed and variable component parts
US9538388B2 (en) * 2006-05-12 2017-01-03 Shared Spectrum Company Method and system for dynamic spectrum access
US7564816B2 (en) * 2006-05-12 2009-07-21 Shared Spectrum Company Method and system for determining spectrum availability within a network
EP2020086A2 (en) * 2006-05-22 2009-02-04 ViaSat, Inc. Segmented code division multiple access
US7720485B2 (en) 2006-07-14 2010-05-18 Qualcomm Incorporated Methods and apparatus related to assignment in a wireless communications system
US7724853B2 (en) * 2006-07-14 2010-05-25 Qualcomm Incorporated Enabling mobile switched antennas
US8027249B2 (en) 2006-10-18 2011-09-27 Shared Spectrum Company Methods for using a detector to monitor and detect channel occupancy
US7992070B2 (en) * 2006-12-27 2011-08-02 Nec Laboratories America, Inc. Bit-interleaved LDPC-coded modulation for high-speed optical transmission
US8997170B2 (en) 2006-12-29 2015-03-31 Shared Spectrum Company Method and device for policy-based control of radio
US7610036B2 (en) * 2007-01-08 2009-10-27 Mitsubishi Electric Research Laboratories, Inc. Space-time-frequency sensing of RF spectrum in cognitive radios
US8825065B2 (en) * 2007-01-19 2014-09-02 Wi-Lan, Inc. Transmit power dependent reduced emissions from a wireless transceiver
US8290447B2 (en) 2007-01-19 2012-10-16 Wi-Lan Inc. Wireless transceiver with reduced transmit emissions
US8184653B2 (en) 2007-08-15 2012-05-22 Shared Spectrum Company Systems and methods for a cognitive radio having adaptable characteristics
US8055204B2 (en) 2007-08-15 2011-11-08 Shared Spectrum Company Methods for detecting and classifying signals transmitted over a radio frequency spectrum
KR101048438B1 (en) * 2007-09-13 2011-07-11 삼성전자주식회사 Signal-to-interference-and-noise ratio estimation apparatus and method in a wireless communication system
US8213582B2 (en) 2008-03-14 2012-07-03 Broadcom Europe Limited Coupling signal processing circuitry with a wireline communications medium
US20110097993A1 (en) * 2008-06-12 2011-04-28 Sharp Kabushiki Kaisha Relay apparatus, communication system and relay method
US7602220B1 (en) 2008-06-24 2009-10-13 Gigle Semiconductor, Ltd. Resistor-input transconductor including common-mode compensation
EP2319260A2 (en) * 2008-08-19 2011-05-11 Shared Spectrum Company Method and system for dynamic spectrum access using specialty detectors and improved networking
US8345803B2 (en) * 2008-10-02 2013-01-01 Qualcomm Incorporated Optimized finger assignment for improved multicarrier throughput
EP2182645B1 (en) * 2008-10-29 2014-07-02 Thales Alenia Space Italia S.p.A. Method and system for spread spectrum signal acquisition
US9001679B2 (en) * 2011-11-07 2015-04-07 Qualcomm Incorporated Supporting voice for flexible bandwidth systems
CN104185187B (en) * 2013-05-27 2017-12-22 华为终端有限公司 LTE and control method of a terminal device and coexistence WiFi

Citations (83)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6173094B2 (en) *
US4229831A (en) * 1978-12-22 1980-10-21 Burroughs Corporation Drift compensated fiber optic-receiver
US4535459A (en) * 1983-05-26 1985-08-13 Rockwell International Corporation Signal detection apparatus
US4636859A (en) * 1984-03-09 1987-01-13 Thomson Csf Didon digital demodulator
US4710022A (en) * 1983-10-31 1987-12-01 Fujitsu Limited Method and apparatus for measuring chromatic dispersion coefficient
US5224183A (en) * 1992-07-23 1993-06-29 Alcatel Network Systems, Inc. Multiple wavelength division multiplexing signal compensation system and method using same
US5225922A (en) * 1991-11-21 1993-07-06 At&T Bell Laboratories Optical transmission system equalizer
US5267071A (en) * 1991-09-03 1993-11-30 Scientific-Atlanta, Inc. Signal level control circuitry for a fiber communications system
US5299048A (en) * 1989-08-31 1994-03-29 Fujitsu Limited Optical amplifier and optical communication system provided with the optical amplifier
US5321541A (en) * 1991-12-12 1994-06-14 At&T Bell Laboratories Passive optical communication network with broadband upgrade
US5455703A (en) * 1992-06-24 1995-10-03 Litton Systems, Inc. Fiber optic transceiver with integrated coupler
US5479447A (en) * 1993-05-03 1995-12-26 The Board Of Trustees Of The Leland Stanford, Junior University Method and apparatus for adaptive, variable bandwidth, high-speed data transmission of a multicarrier signal over digital subscriber lines
US5559625A (en) * 1992-09-14 1996-09-24 British Telecommunications Public Limited Company Distributive communications network
US5613210A (en) * 1992-11-19 1997-03-18 U.S. Philips Corporation Telecommunication network for transmitting information to a plurality of stations over a single channel
US5726784A (en) * 1995-05-11 1998-03-10 Ciena Corp. WDM optical communication system with remodulators and diverse optical transmitters
US5737118A (en) * 1995-05-08 1998-04-07 Fujitsu Limited Optical amplifying apparatus
US5778116A (en) * 1997-01-23 1998-07-07 Tomich; John L. Photonic home area network fiber/power insertion apparatus
US5790285A (en) * 1996-05-21 1998-08-04 Lucent Technologies Inc. Lightwave communication monitoring system
US5812290A (en) * 1995-12-15 1998-09-22 Nec Corporation Optical switching unit and control method for same
US5877881A (en) * 1996-04-19 1999-03-02 Fujitsu Ltd. Optical transmission system
US5903613A (en) * 1996-01-23 1999-05-11 Seiko Epson Corporation Data reception device, data reception method and electronic equipment
US5914799A (en) * 1995-09-15 1999-06-22 Koninklijke Ptt Nederland N.V. Optical network
US5914794A (en) * 1996-12-31 1999-06-22 Mci Communications Corporation Method of and apparatus for detecting and reporting faults in an all-optical communications system
US5936753A (en) * 1996-11-19 1999-08-10 Fujitsu Limited Optical network system
US5940209A (en) * 1997-03-18 1999-08-17 Lucent Technologies Inc. Interactive optical fiber amplifier, system and method
US5963350A (en) * 1994-03-29 1999-10-05 British Telecommunications Public Limited Company Optical telecommunications network
US5995694A (en) * 1996-06-21 1999-11-30 The Furukawa Electric Co., Ltd. Wavelength division multiplex communication link for optical transmission
US6005702A (en) * 1996-02-23 1999-12-21 Kokusai Denshin Denwa Kabushiki-Kaisha Optical transmission device, WDM optical transmission apparatus, and optical transmission system using return-to-zero optical pulses
US6021245A (en) * 1997-07-29 2000-02-01 Lucent Technologies Inc. Method and optical transmission system for compensating dispersion in optical transmission paths
US6038062A (en) * 1995-10-03 2000-03-14 Hitachi, Ltd. Optical amplifier, method of controlling the output light from the optical amplifier, optical transmission system and method of controlling an optical transmission path
US6075634A (en) * 1998-08-05 2000-06-13 Jds Uniphase Corporation, Ubp Gigabit data rate extended range fiber optic communication system and transponder therefor
US6078414A (en) * 1996-12-05 2000-06-20 Nec Corporation Optical transmitter system
US6081360A (en) * 1997-08-20 2000-06-27 Fujitsu Limited Method and apparatus for optimizing dispersion in an optical fiber transmission line in accordance with an optical signal power level
US6084694A (en) * 1997-08-27 2000-07-04 Nortel Networks Corporation WDM optical network with passive pass-through at each node
US6088152A (en) * 1999-03-08 2000-07-11 Lucent Technologies Inc. Optical amplifier arranged to offset Raman gain
US6108074A (en) * 1996-10-01 2000-08-22 Bloom; Cary Optical switching assembly for testing fiber optic device
US6122095A (en) * 1997-08-29 2000-09-19 Lucent Technologies Inc. Wavelength-selective and loss-less optical add/drop multiplexer
US6151334A (en) * 1995-10-05 2000-11-21 Silicon Image, Inc. System and method for sending multiple data signals over a serial link
US6157477A (en) * 1998-05-27 2000-12-05 Mci Communications Corporations Bidirectional dispersion compensation system
US6160614A (en) * 1998-05-19 2000-12-12 Ando Electric Co., Ltd. Method, apparatus and computer program product for classification of measured data from multi-core optical fiber
US6163392A (en) * 1997-05-23 2000-12-19 Ciena Corporation Distributed intelligence wavelength division multiplexed network
US6163636A (en) * 1999-01-19 2000-12-19 Lucent Technologies Inc. Optical communication system using multiple-order Raman amplifiers
US6173094B1 (en) * 1998-03-25 2001-01-09 Corning Incorporated Optical-transmission system having a split-gain amplifier and a signal-modifying device
US6177985B1 (en) * 1996-10-01 2001-01-23 Cary Bloom Apparatus and method for testing optical fiber system components
US6198559B1 (en) * 1998-11-20 2001-03-06 Lucent Technologies, Inc. Automatic delay compensation for generating NRZ signals from RZ signals in communications networks
US6229599B1 (en) * 1997-02-13 2001-05-08 Cselt - Centro Studi E Laboratori Telecomunicazioni S.P.A. Apparatus for measuring characteristics of an optical fiber
US6236499B1 (en) * 1999-04-15 2001-05-22 Nortel Networks Limited Highly scalable modular optical amplifier based subsystem
US6236481B1 (en) * 1999-06-09 2001-05-22 Astarte Fiber Networks, Inc. Method and apparatus for providing loss equalization and adjustment in a fiber optic network
US6246510B1 (en) * 1999-04-28 2001-06-12 Marconi Communications, Inc. Light amplification apparatus with automatic monitoring and controls
US20010005271A1 (en) * 1999-12-23 2001-06-28 Olivier Leclerc Device for applying time-delays to optical signals
US6259553B1 (en) * 1996-05-13 2001-07-10 Fujitsu Limited Optical communication system and optical amplifier
US6259693B1 (en) * 1997-08-28 2001-07-10 Ascend Communications, Inc. Cell combination to utilize available switch bandwidth
US6259845B1 (en) * 1998-08-20 2001-07-10 Ciena Corporation Dispersion compensating element having an adjustable dispersion
US6259554B1 (en) * 1998-06-26 2001-07-10 Sumitomo Electric Industries, Ltd. Optical amplifier repeater system
US20010007605A1 (en) * 2000-01-11 2001-07-12 Shinya Inagaki Apparatus and method of compensating for wavelength dispersion of optical transmission line
US20010009468A1 (en) * 1999-06-22 2001-07-26 Fee John Arthur Method and system for compensating for chromatic dispersion in an optical network
US6272185B1 (en) * 1998-05-04 2001-08-07 Nortel Networks Limited Method and apparatus for performing data pulse detection
US6275315B1 (en) * 1997-08-28 2001-08-14 Samsung Electronics Co., Ltd. Apparatus for compensating for dispersion of optical fiber in an optical line
US20010014104A1 (en) * 2000-02-09 2001-08-16 Bottorff Paul A. 10 Gigabit ethernet mappings for a common LAN/WAN PMD interface with a simple universal physical medium dependent interface
US6288813B1 (en) * 1998-03-25 2001-09-11 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Apparatus and method for effecting data transfer between data systems
US6288811B1 (en) * 2000-10-17 2001-09-11 Seneca Networks WDM optical communication system with channels supporting multiple data formats
US6307656B2 (en) * 1998-01-30 2001-10-23 Fujitsu Limited Bi-directional wavelength switching device and wavelength demultiplexing/multiplexing device
US6317231B1 (en) * 1998-09-04 2001-11-13 Lucent Technologies Inc. Optical monitoring apparatus and method for network provisioning and maintenance
US6317255B1 (en) * 1998-04-28 2001-11-13 Lucent Technologies Inc. Method and apparatus for controlling optical signal power in response to faults in an optical fiber path
US6323950B1 (en) * 1999-09-28 2001-11-27 Lucent Technologies, Inc. Chromatic dispersion measurement for optical components
US6327060B1 (en) * 1997-03-04 2001-12-04 Kokusai Denshin Denwa Kabushiki Kaisha Optical transmission system, optically branching apparatus and optical signal processing apparatus
US20020012152A1 (en) * 2000-07-21 2002-01-31 Broadcom Corporation Methods and systems for digitally processing optical data signals
US20020015220A1 (en) * 2000-07-10 2002-02-07 Serguei Papernyl Cascaded pumping system and method for producing distributed raman amplification in optical fiber telecommunication systems
US6356384B1 (en) * 1998-03-24 2002-03-12 Xtera Communications Inc. Broadband amplifier and communication system
US6359729B1 (en) * 1998-11-17 2002-03-19 Corvis Corporation Optical communication system and component control architectures and methods
US20020034197A1 (en) * 1998-11-17 2002-03-21 Tornetta Anthony G. High speed linking module
US20020044324A1 (en) * 2000-08-25 2002-04-18 Fujitsu Limited Optical communication system, method for supplying pump light, and distributed raman amplifying apparatus
US20020044317A1 (en) * 2000-08-21 2002-04-18 Guido Gentner Control method and optical data transmission path for compensating changes in SRS-induced power exchange
US20020048287A1 (en) * 1997-10-08 2002-04-25 Silvers John Leroy System and method of disharmonic frequency multiplexing
US20020051468A1 (en) * 1998-07-22 2002-05-02 Yoram Ofek Time-based grooming and degrooming methods with common time reference for optical networks
US6388801B1 (en) * 2000-08-30 2002-05-14 Fujitsu Limited Optical amplification apparatus utilizing Raman amplification and controlling method thereof
US6396853B1 (en) * 1998-05-28 2002-05-28 Nortel Networks Limited Providing data services to telecommunications user terminals
US20020063948A1 (en) * 1998-06-16 2002-05-30 Islam Mohammed N. All band amplifier
US20020064181A1 (en) * 1998-07-22 2002-05-30 Yoram Ofek Multi-terabit SONET switching with common time reference
US20020075903A1 (en) * 2000-12-19 2002-06-20 Nortel Networks Limited Multiplexing SONET /SDH data streams using independent encoding schemes
US20020080809A1 (en) * 2000-12-21 2002-06-27 James Nicholson System and method for multiplexing synchronous digital data streams
US6510133B1 (en) * 1997-05-30 2003-01-21 Matsushita Electric Industrial Co., Ltd. Multi-carrier transmission method and data transmitter
US6519082B2 (en) * 2001-02-26 2003-02-11 Redc Optical Networks Ltd. Apparatus and method for a self-adjusting Raman amplifier

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6084919A (en) 1998-01-30 2000-07-04 Motorola, Inc. Communication unit having spectral adaptability
US7230908B2 (en) 2000-07-24 2007-06-12 Viasat, Inc. Dynamic link assignment in a communication system
JP2002111631A (en) * 2000-10-04 2002-04-12 Yrp Mobile Telecommunications Key Tech Res Lab Co Ltd System and apparatus for radio communication

Patent Citations (83)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6173094B2 (en) *
US4229831A (en) * 1978-12-22 1980-10-21 Burroughs Corporation Drift compensated fiber optic-receiver
US4535459A (en) * 1983-05-26 1985-08-13 Rockwell International Corporation Signal detection apparatus
US4710022A (en) * 1983-10-31 1987-12-01 Fujitsu Limited Method and apparatus for measuring chromatic dispersion coefficient
US4636859A (en) * 1984-03-09 1987-01-13 Thomson Csf Didon digital demodulator
US5299048A (en) * 1989-08-31 1994-03-29 Fujitsu Limited Optical amplifier and optical communication system provided with the optical amplifier
US5267071A (en) * 1991-09-03 1993-11-30 Scientific-Atlanta, Inc. Signal level control circuitry for a fiber communications system
US5225922A (en) * 1991-11-21 1993-07-06 At&T Bell Laboratories Optical transmission system equalizer
US5321541A (en) * 1991-12-12 1994-06-14 At&T Bell Laboratories Passive optical communication network with broadband upgrade
US5455703A (en) * 1992-06-24 1995-10-03 Litton Systems, Inc. Fiber optic transceiver with integrated coupler
US5224183A (en) * 1992-07-23 1993-06-29 Alcatel Network Systems, Inc. Multiple wavelength division multiplexing signal compensation system and method using same
US5559625A (en) * 1992-09-14 1996-09-24 British Telecommunications Public Limited Company Distributive communications network
US5613210A (en) * 1992-11-19 1997-03-18 U.S. Philips Corporation Telecommunication network for transmitting information to a plurality of stations over a single channel
US5479447A (en) * 1993-05-03 1995-12-26 The Board Of Trustees Of The Leland Stanford, Junior University Method and apparatus for adaptive, variable bandwidth, high-speed data transmission of a multicarrier signal over digital subscriber lines
US5963350A (en) * 1994-03-29 1999-10-05 British Telecommunications Public Limited Company Optical telecommunications network
US5737118A (en) * 1995-05-08 1998-04-07 Fujitsu Limited Optical amplifying apparatus
US5726784A (en) * 1995-05-11 1998-03-10 Ciena Corp. WDM optical communication system with remodulators and diverse optical transmitters
US5914799A (en) * 1995-09-15 1999-06-22 Koninklijke Ptt Nederland N.V. Optical network
US6038062A (en) * 1995-10-03 2000-03-14 Hitachi, Ltd. Optical amplifier, method of controlling the output light from the optical amplifier, optical transmission system and method of controlling an optical transmission path
US6151334A (en) * 1995-10-05 2000-11-21 Silicon Image, Inc. System and method for sending multiple data signals over a serial link
US5812290A (en) * 1995-12-15 1998-09-22 Nec Corporation Optical switching unit and control method for same
US5903613A (en) * 1996-01-23 1999-05-11 Seiko Epson Corporation Data reception device, data reception method and electronic equipment
US6005702A (en) * 1996-02-23 1999-12-21 Kokusai Denshin Denwa Kabushiki-Kaisha Optical transmission device, WDM optical transmission apparatus, and optical transmission system using return-to-zero optical pulses
US5877881A (en) * 1996-04-19 1999-03-02 Fujitsu Ltd. Optical transmission system
US6259553B1 (en) * 1996-05-13 2001-07-10 Fujitsu Limited Optical communication system and optical amplifier
US5790285A (en) * 1996-05-21 1998-08-04 Lucent Technologies Inc. Lightwave communication monitoring system
US5995694A (en) * 1996-06-21 1999-11-30 The Furukawa Electric Co., Ltd. Wavelength division multiplex communication link for optical transmission
US6177985B1 (en) * 1996-10-01 2001-01-23 Cary Bloom Apparatus and method for testing optical fiber system components
US6108074A (en) * 1996-10-01 2000-08-22 Bloom; Cary Optical switching assembly for testing fiber optic device
US5936753A (en) * 1996-11-19 1999-08-10 Fujitsu Limited Optical network system
US6078414A (en) * 1996-12-05 2000-06-20 Nec Corporation Optical transmitter system
US5914794A (en) * 1996-12-31 1999-06-22 Mci Communications Corporation Method of and apparatus for detecting and reporting faults in an all-optical communications system
US5778116A (en) * 1997-01-23 1998-07-07 Tomich; John L. Photonic home area network fiber/power insertion apparatus
US6229599B1 (en) * 1997-02-13 2001-05-08 Cselt - Centro Studi E Laboratori Telecomunicazioni S.P.A. Apparatus for measuring characteristics of an optical fiber
US6327060B1 (en) * 1997-03-04 2001-12-04 Kokusai Denshin Denwa Kabushiki Kaisha Optical transmission system, optically branching apparatus and optical signal processing apparatus
US5940209A (en) * 1997-03-18 1999-08-17 Lucent Technologies Inc. Interactive optical fiber amplifier, system and method
US6163392A (en) * 1997-05-23 2000-12-19 Ciena Corporation Distributed intelligence wavelength division multiplexed network
US6510133B1 (en) * 1997-05-30 2003-01-21 Matsushita Electric Industrial Co., Ltd. Multi-carrier transmission method and data transmitter
US6021245A (en) * 1997-07-29 2000-02-01 Lucent Technologies Inc. Method and optical transmission system for compensating dispersion in optical transmission paths
US6081360A (en) * 1997-08-20 2000-06-27 Fujitsu Limited Method and apparatus for optimizing dispersion in an optical fiber transmission line in accordance with an optical signal power level
US6084694A (en) * 1997-08-27 2000-07-04 Nortel Networks Corporation WDM optical network with passive pass-through at each node
US6275315B1 (en) * 1997-08-28 2001-08-14 Samsung Electronics Co., Ltd. Apparatus for compensating for dispersion of optical fiber in an optical line
US6259693B1 (en) * 1997-08-28 2001-07-10 Ascend Communications, Inc. Cell combination to utilize available switch bandwidth
US6122095A (en) * 1997-08-29 2000-09-19 Lucent Technologies Inc. Wavelength-selective and loss-less optical add/drop multiplexer
US20020048287A1 (en) * 1997-10-08 2002-04-25 Silvers John Leroy System and method of disharmonic frequency multiplexing
US6307656B2 (en) * 1998-01-30 2001-10-23 Fujitsu Limited Bi-directional wavelength switching device and wavelength demultiplexing/multiplexing device
US6356384B1 (en) * 1998-03-24 2002-03-12 Xtera Communications Inc. Broadband amplifier and communication system
US6173094B1 (en) * 1998-03-25 2001-01-09 Corning Incorporated Optical-transmission system having a split-gain amplifier and a signal-modifying device
US6288813B1 (en) * 1998-03-25 2001-09-11 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Apparatus and method for effecting data transfer between data systems
US6317255B1 (en) * 1998-04-28 2001-11-13 Lucent Technologies Inc. Method and apparatus for controlling optical signal power in response to faults in an optical fiber path
US6272185B1 (en) * 1998-05-04 2001-08-07 Nortel Networks Limited Method and apparatus for performing data pulse detection
US6160614A (en) * 1998-05-19 2000-12-12 Ando Electric Co., Ltd. Method, apparatus and computer program product for classification of measured data from multi-core optical fiber
US6157477A (en) * 1998-05-27 2000-12-05 Mci Communications Corporations Bidirectional dispersion compensation system
US6396853B1 (en) * 1998-05-28 2002-05-28 Nortel Networks Limited Providing data services to telecommunications user terminals
US20020063948A1 (en) * 1998-06-16 2002-05-30 Islam Mohammed N. All band amplifier
US6259554B1 (en) * 1998-06-26 2001-07-10 Sumitomo Electric Industries, Ltd. Optical amplifier repeater system
US20020064181A1 (en) * 1998-07-22 2002-05-30 Yoram Ofek Multi-terabit SONET switching with common time reference
US20020051468A1 (en) * 1998-07-22 2002-05-02 Yoram Ofek Time-based grooming and degrooming methods with common time reference for optical networks
US6075634A (en) * 1998-08-05 2000-06-13 Jds Uniphase Corporation, Ubp Gigabit data rate extended range fiber optic communication system and transponder therefor
US6259845B1 (en) * 1998-08-20 2001-07-10 Ciena Corporation Dispersion compensating element having an adjustable dispersion
US6317231B1 (en) * 1998-09-04 2001-11-13 Lucent Technologies Inc. Optical monitoring apparatus and method for network provisioning and maintenance
US6359729B1 (en) * 1998-11-17 2002-03-19 Corvis Corporation Optical communication system and component control architectures and methods
US20020034197A1 (en) * 1998-11-17 2002-03-21 Tornetta Anthony G. High speed linking module
US6198559B1 (en) * 1998-11-20 2001-03-06 Lucent Technologies, Inc. Automatic delay compensation for generating NRZ signals from RZ signals in communications networks
US6163636A (en) * 1999-01-19 2000-12-19 Lucent Technologies Inc. Optical communication system using multiple-order Raman amplifiers
US6088152A (en) * 1999-03-08 2000-07-11 Lucent Technologies Inc. Optical amplifier arranged to offset Raman gain
US6236499B1 (en) * 1999-04-15 2001-05-22 Nortel Networks Limited Highly scalable modular optical amplifier based subsystem
US6246510B1 (en) * 1999-04-28 2001-06-12 Marconi Communications, Inc. Light amplification apparatus with automatic monitoring and controls
US6236481B1 (en) * 1999-06-09 2001-05-22 Astarte Fiber Networks, Inc. Method and apparatus for providing loss equalization and adjustment in a fiber optic network
US20010009468A1 (en) * 1999-06-22 2001-07-26 Fee John Arthur Method and system for compensating for chromatic dispersion in an optical network
US6323950B1 (en) * 1999-09-28 2001-11-27 Lucent Technologies, Inc. Chromatic dispersion measurement for optical components
US20010005271A1 (en) * 1999-12-23 2001-06-28 Olivier Leclerc Device for applying time-delays to optical signals
US20010007605A1 (en) * 2000-01-11 2001-07-12 Shinya Inagaki Apparatus and method of compensating for wavelength dispersion of optical transmission line
US20010014104A1 (en) * 2000-02-09 2001-08-16 Bottorff Paul A. 10 Gigabit ethernet mappings for a common LAN/WAN PMD interface with a simple universal physical medium dependent interface
US20020015220A1 (en) * 2000-07-10 2002-02-07 Serguei Papernyl Cascaded pumping system and method for producing distributed raman amplification in optical fiber telecommunication systems
US20020012152A1 (en) * 2000-07-21 2002-01-31 Broadcom Corporation Methods and systems for digitally processing optical data signals
US20020044317A1 (en) * 2000-08-21 2002-04-18 Guido Gentner Control method and optical data transmission path for compensating changes in SRS-induced power exchange
US20020044324A1 (en) * 2000-08-25 2002-04-18 Fujitsu Limited Optical communication system, method for supplying pump light, and distributed raman amplifying apparatus
US6388801B1 (en) * 2000-08-30 2002-05-14 Fujitsu Limited Optical amplification apparatus utilizing Raman amplification and controlling method thereof
US6288811B1 (en) * 2000-10-17 2001-09-11 Seneca Networks WDM optical communication system with channels supporting multiple data formats
US20020075903A1 (en) * 2000-12-19 2002-06-20 Nortel Networks Limited Multiplexing SONET /SDH data streams using independent encoding schemes
US20020080809A1 (en) * 2000-12-21 2002-06-27 James Nicholson System and method for multiplexing synchronous digital data streams
US6519082B2 (en) * 2001-02-26 2003-02-11 Redc Optical Networks Ltd. Apparatus and method for a self-adjusting Raman amplifier

Cited By (120)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7197690B2 (en) 2002-05-31 2007-03-27 Broadcom Corporation Bandwidth efficient coded modulation scheme based on MLC (multi-level code) signals having multiple maps
US7577207B2 (en) 2002-07-03 2009-08-18 Dtvg Licensing, Inc. Bit labeling for amplitude phase shift constellation used with low density parity check (LDPC) codes
US8102947B2 (en) 2002-07-03 2012-01-24 Dtvg Licensing, Inc. Bit labeling for amplitude phase shift constellation used with low density parity check (LDPC) codes
US7398455B2 (en) 2002-07-03 2008-07-08 The Directv Group, Inc. Method and system for decoding low density parity check (LDPC) codes
US7962830B2 (en) 2002-07-03 2011-06-14 Dtvg Licensing, Inc. Method and system for routing in low density parity check (LDPC) decoders
US20050271160A1 (en) * 2002-07-03 2005-12-08 Mustafa Eroz Bit labeling for amplitude phase shift constellation used with low density parity check (LDPC) codes
US20070168834A1 (en) * 2002-07-03 2007-07-19 Mustafa Eroz Method and system for routing in low density parity check (LDPC) decoders
US20040054960A1 (en) * 2002-07-03 2004-03-18 Mustafa Eroz Method and system for providing low density parity check (LDPC) encoding
US7424662B2 (en) 2002-07-03 2008-09-09 The Directv Group, Inc. Method and system for providing low density parity check (LDPC) encoding
US6963622B2 (en) * 2002-07-03 2005-11-08 The Directv Group, Inc. Bit labeling for amplitude phase shift constellation used with low density parity check (LDPC) codes
US20070113142A1 (en) * 2002-07-03 2007-05-17 Mustafa Eroz Method and system for providing low density parity check (LDPC) encoding
US7954036B2 (en) 2002-07-03 2011-05-31 Dtvg Licensing, Inc. Method and system for providing low density parity check (LDPC) encoding
US20040086059A1 (en) * 2002-07-03 2004-05-06 Hughes Electronics Bit labeling for amplitude phase shift constellation used with low density parity check (LDPC) codes
US7191378B2 (en) 2002-07-03 2007-03-13 The Directv Group, Inc. Method and system for providing low density parity check (LDPC) encoding
US20090187811A1 (en) * 2002-07-03 2009-07-23 The Directv Group, Inc. Method and system for providing low density parity check (ldpc) encoding
US7864869B2 (en) 2002-07-26 2011-01-04 Dtvg Licensing, Inc. Satellite communication system utilizing low density parity check codes
US20080082895A1 (en) * 2002-07-26 2008-04-03 The Directv Group, Inc. Method and system for generating low density parity check codes
US20050063484A1 (en) * 2002-07-26 2005-03-24 Mustafa Eroz Satellite communincation system utilizing low density parity check codes
US8095854B2 (en) 2002-07-26 2012-01-10 Dtvg Licensing, Inc. Method and system for generating low density parity check codes
US20060164292A1 (en) * 2002-12-03 2006-07-27 Josef Buechler Radar system comprising integrated data transmission
US20060116078A1 (en) * 2002-12-24 2006-06-01 Matsushita Electric Industrial Co., Ltd. Radio communication apparatus and radio transmission method
US7215927B2 (en) * 2002-12-24 2007-05-08 Matsushita Electric Industrial Co., Ltd. Radio communication apparatus and radio transmission method
WO2005015815A2 (en) * 2003-08-06 2005-02-17 Intel Corporation Technique to select transmission parameters
US20050030887A1 (en) * 2003-08-06 2005-02-10 Jacobsen Eric A. Technique to select transmission parameters
US7903538B2 (en) 2003-08-06 2011-03-08 Intel Corporation Technique to select transmission parameters
WO2005015815A3 (en) * 2003-08-06 2005-06-02 Intel Corp Technique to select transmission parameters
US20050079840A1 (en) * 2003-10-11 2005-04-14 Visteon Global Technologies, Inc. Method for controlling the selectivity of a tuner in a variable bandwidth system
US20050085223A1 (en) * 2003-10-20 2005-04-21 Accton Technology Corporation System and method for multi-path simulation
US7383487B2 (en) 2004-01-10 2008-06-03 Broadcom Corporation IPHD (iterative parallel hybrid decoding) of various MLC (multi-level code) signals
EP1553706A1 (en) * 2004-01-10 2005-07-13 Broadcom Corporation Bandwidth efficient LDPC (low density parity check) coded modulation scheme based on MLC (multi-level code) signals
EP1745571A2 (en) * 2004-05-01 2007-01-24 Waltical Solutions, Inc. Methods and apparatus for multi-carrier communications with variable channel bandwidth
EP1745571A4 (en) * 2004-05-01 2011-11-16 Ditromossi Remote Bv L L C Methods and apparatus for multi-carrier communications with variable channel bandwidth
EP3193469A1 (en) * 2004-05-01 2017-07-19 Callahan Cellular LLC Methods and apparatus for multi-carrier communications with variable channel bandwidth
US20140301220A1 (en) * 2004-06-30 2014-10-09 Neocific, Inc. Method and apparatus for interference control in a multi-cell communication system
US20080039129A1 (en) * 2004-06-30 2008-02-14 Xiaodong Li Methods and Apparatus for Power Control in Multi-carier Wireless Systems
US9755809B2 (en) * 2004-06-30 2017-09-05 Amazon Technologies, Inc. Method and apparatus for interference control in a multi-cell communication system
US8031686B2 (en) 2004-06-30 2011-10-04 Neocific, Inc. Methods and apparatus for power control in multi-carrier wireless systems
EP1615367A1 (en) * 2004-07-10 2006-01-11 Samsung Electronics Co., Ltd. Method of allocating subcarriers on the downlink of a CDMA system
WO2006019441A1 (en) * 2004-07-19 2006-02-23 Telefonaktiebolaget Lm Ericsson (Publ) Selective multicarrier cdma network
US8085887B2 (en) * 2004-09-30 2011-12-27 Infineon Technologies Ag Method and receiver circuit for reducing RFI interference
US20060083325A1 (en) * 2004-09-30 2006-04-20 Infineon Technologies Ag Method and receiver circuit for reducing RFI interference
US7877064B2 (en) * 2004-11-01 2011-01-25 General Instrument Corporation Methods, apparatus and systems for terrestrial wireless broadcast of digital data to stationary receivers
US20060092902A1 (en) * 2004-11-01 2006-05-04 General Instrument Corporation Methods, apparatus and systems for terrestrial wireless broadcast of digital data to stationary receivers
US20060131379A1 (en) * 2004-12-21 2006-06-22 Junichi Aoki Physical distribution management system and method for customized products
US7471702B2 (en) 2005-03-09 2008-12-30 Qualcomm Incorporated Methods and apparatus for implementing, using, transmitting, and/or receiving signals at least some of which include intentional null tones
US8325826B2 (en) 2005-03-09 2012-12-04 Qualcomm Incorporated Methods and apparatus for transmitting signals facilitating antenna control
US7826807B2 (en) 2005-03-09 2010-11-02 Qualcomm Incorporated Methods and apparatus for antenna control in a wireless terminal
US20060205356A1 (en) * 2005-03-09 2006-09-14 Rajiv Laroia Methods and apparatus for antenna control in a wireless terminal
US20060205355A1 (en) * 2005-03-09 2006-09-14 Rajiv Laroia Methods and apparatus for transmitting signals facilitating antenna control
US20060203709A1 (en) * 2005-03-09 2006-09-14 Rajiv Laroia Methods and apparatus for implementing, using, transmitting, and/or receiving signals at least some of which include intentional null tones
WO2006098992A1 (en) * 2005-03-09 2006-09-21 Qualcomm Flarion Technologies, Inc. Methods and apparatus for transmitting signals in a multicarrier system
US20090147869A1 (en) * 2005-08-22 2009-06-11 Matsushita Electric Industrial Co., Ltd. Communication terminal apparatus, base station apparatus and reception quality reporting method
US7986612B2 (en) * 2005-08-22 2011-07-26 Panasonic Corporation Communication terminal apparatus, base station apparatus and reception quality reporting method
US20070076666A1 (en) * 2005-10-03 2007-04-05 Riveiro Juan C Multi-Wideband Communications over Power Lines
US20070075843A1 (en) * 2005-10-03 2007-04-05 Riveiro Juan C Multi-Wideband Communications over Power Lines
US20070229231A1 (en) * 2005-10-03 2007-10-04 Hurwitz Jonathan E D Multi-Wideband Communications over Multiple Mediums within a Network
US20090252209A1 (en) * 2005-10-03 2009-10-08 Juan Carlos Riveiro Power Line Communication Networks and Methods employing Multiple Widebands
US7877078B2 (en) 2005-10-03 2011-01-25 Juan Carlos Riveiro Power line communication networks and methods employing multiple widebands
US7725096B2 (en) 2005-10-03 2010-05-25 Gigle Semiconductor Sl Multi-wideband communications over power lines
US8406239B2 (en) 2005-10-03 2013-03-26 Broadcom Corporation Multi-wideband communications over multiple mediums
US20080130640A1 (en) * 2005-10-03 2008-06-05 Jonathan Ephraim David Hurwitz Multi-Wideband Communications over Multiple Mediums
US8213895B2 (en) 2005-10-03 2012-07-03 Broadcom Europe Limited Multi-wideband communications over multiple mediums within a network
US7899436B2 (en) 2005-10-03 2011-03-01 Juan Carlos Riveiro Multi-wideband communications over power lines
EP1783942A1 (en) * 2005-11-08 2007-05-09 Motorola, Inc. Low-density parity check coding for orthogonal frequency division multiplex systems
US20070118030A1 (en) * 2005-11-22 2007-05-24 Isense Corporation Method and apparatus for analyte data telemetry
US7796708B2 (en) 2006-03-29 2010-09-14 Provigent Ltd. Adaptive receiver loops with weighted decision-directed error
US20080008081A1 (en) * 2006-07-06 2008-01-10 Gigle Semiconductor Inc. Adaptative multi-carrier code division multiple access
US20100265992A1 (en) * 2006-07-06 2010-10-21 Jose Abad Molina Adaptative Multi-Carrier Code Division Multiple Access
US8520715B2 (en) * 2006-07-06 2013-08-27 Broadcom Corporation Adaptative multi-carrier code division multiple access
US7860146B2 (en) * 2006-07-06 2010-12-28 Gigle Networks, Inc. Adaptative multi-carrier code division multiple access
US20080260073A1 (en) * 2006-07-14 2008-10-23 Hui Jin Ecoding and decoding methods and apparatus for use in a wireless communication system
US8225186B2 (en) 2006-07-14 2012-07-17 Qualcomm Incorporated Ecoding and decoding methods and apparatus for use in a wireless communication system
US8885814B2 (en) 2006-07-25 2014-11-11 Broadcom Europe Limited Feedback impedance control for driving a signal
US20080089398A1 (en) * 2006-10-12 2008-04-17 Cormier Daniel R Determining a mode to transmit data
US8019018B2 (en) 2006-10-12 2011-09-13 Powerwave Cognition, Inc. Determining a mode to transmit data
EP2181516A2 (en) * 2006-11-10 2010-05-05 Powerwave Cognition, Inc. Method and apparatus for adjusting waveform parameters for an adaptive air interface waveform
US20080112428A1 (en) * 2006-11-10 2008-05-15 Seidel Scott Y Scheduling for autonomous dynamic spectrum access systems
US7787426B2 (en) 2006-11-10 2010-08-31 Powerwave Cognition, Inc. Adaptive control channel initialization operations for autonomous dynamic spectrum access systems
EP2181516A4 (en) * 2006-11-10 2012-05-23 Powerwave Cognition Inc Method and apparatus for adjusting waveform parameters for an adaptive air interface waveform
US20080112427A1 (en) * 2006-11-10 2008-05-15 Seidel Scott Y Autonomous dynamic spectrum access
US20080113667A1 (en) * 2006-11-10 2008-05-15 Seidel Scott Y Bearer selection and negotiation in autonomous dynamic spectrum access systems
US8718555B2 (en) 2006-11-10 2014-05-06 Powerwave Cognition, Inc. Method and system for using selected bearer channels
US8014783B2 (en) 2006-11-10 2011-09-06 Powerwave Cognition, Inc. Bearer selection and negotiation in autonomous dynamic spectrum access systems
WO2008147447A3 (en) * 2006-11-10 2010-02-18 Powerwave Cognition, Inc. Method and apparatus for adjusting waveform parameters for an adaptive air interface waveform
US8155127B2 (en) 2006-11-10 2012-04-10 Powerwave Cognition, Inc. Autonomous dynamic spectrum access
US20080113624A1 (en) * 2006-11-10 2008-05-15 Seidel Scott Y Method and apparatus for adjusting waveform parameters for an adaptive air interface waveform
US20080112426A1 (en) * 2006-11-10 2008-05-15 Seidel Scott Y Adaptive control channel initialization operations for autonomous dynamic spectrum access systems
US20080112341A1 (en) * 2006-11-10 2008-05-15 Seidel Scott Y Method and system for using selected bearer channels
US8208873B2 (en) * 2006-11-10 2012-06-26 Powerwave Cognition, Inc. Method and apparatus for adjusting waveform parameters for an adaptive air interface waveform
US20080117896A1 (en) * 2006-11-21 2008-05-22 Veronica Romero Network repeater
US7808985B2 (en) 2006-11-21 2010-10-05 Gigle Networks Sl Network repeater
US7839952B2 (en) 2006-12-05 2010-11-23 Provigent Ltd Data rate coordination in protected variable-rate links
US8259591B2 (en) * 2007-01-30 2012-09-04 Samsung Electronics Co., Ltd. Apparatus and method for receiving signal in a communication system
US20080212549A1 (en) * 2007-01-30 2008-09-04 Samsung Electronics Co., Ltd. Apparatus and method for receiving signal in a communication system
US8364179B2 (en) 2007-04-13 2013-01-29 Provigent Ltd. Feedback-based management of variable-rate communication links
US8315574B2 (en) * 2007-04-13 2012-11-20 Broadcom Corporation Management of variable-rate communication links
US20080254749A1 (en) * 2007-04-13 2008-10-16 Provigent Ltd. Management of variable-rate communication links
US8385839B2 (en) 2007-04-13 2013-02-26 Provigent Ltd. Message-based management of variable-rate communication links
US8081727B2 (en) * 2007-04-20 2011-12-20 Kabushiki Kaisha Toshiba Radio communication apparatus and system
US7821938B2 (en) 2007-04-20 2010-10-26 Provigent Ltd. Adaptive coding and modulation for synchronous connections
US20080260084A1 (en) * 2007-04-20 2008-10-23 Kabushiki Kaisha Toshiba Radio communication apparatus and system
US8001445B2 (en) 2007-08-13 2011-08-16 Provigent Ltd. Protected communication link with improved protection indication
US8040985B2 (en) 2007-10-09 2011-10-18 Provigent Ltd Decoding of forward error correction codes in the presence of phase noise
US8351552B2 (en) 2007-10-09 2013-01-08 Provigent Ltd. Decoding of forward error correction codes in the presence of phase noise and thermal noise
US8483154B2 (en) 2008-02-06 2013-07-09 Nec Corporation Subcarrier allocation method and apparatus thereof
US8629769B2 (en) 2008-08-28 2014-01-14 Isense Corporation Method and system for communication between wireless devices
US20100052899A1 (en) * 2008-08-28 2010-03-04 Isense Corporation Method and system for communication between wireless devices
US7795973B2 (en) 2008-10-13 2010-09-14 Gigle Networks Ltd. Programmable gain amplifier
US20100117734A1 (en) * 2008-10-13 2010-05-13 Jonathan Ephraim David Hurwitz Programmable Gain Amplifier and Transconductance Compensation System
US7956689B2 (en) 2008-10-13 2011-06-07 Broadcom Corporation Programmable gain amplifier and transconductance compensation system
US9591563B2 (en) * 2009-07-01 2017-03-07 Telefonaktiebolaget Lm Ericsson (Publ) Power efficient data transmission
US20110003609A1 (en) * 2009-07-01 2011-01-06 Sundstroem Lars Power Efficient Data Transmission
US8768373B2 (en) * 2011-11-07 2014-07-01 Qualcomm Incorporated Adaptive flexible bandwidth wireless systems
US9220101B2 (en) 2011-11-07 2015-12-22 Qualcomm Incorporated Signaling and traffic carrier splitting for wireless communications systems
US9516531B2 (en) 2011-11-07 2016-12-06 Qualcomm Incorporated Assistance information for flexible bandwidth carrier mobility methods, systems, and devices
US9532251B2 (en) 2011-11-07 2016-12-27 Qualcomm Incorporated Bandwidth information determination for flexible bandwidth carriers
US9848339B2 (en) 2011-11-07 2017-12-19 Qualcomm Incorporated Voice service solutions for flexible bandwidth systems
US20130115967A1 (en) * 2011-11-07 2013-05-09 Qualcomm Incorporated Adaptive flexible bandwidth wireless systems
US20140098782A1 (en) * 2012-10-05 2014-04-10 Sierra Wireless. Inc. Enhancement for lte communication systems
US20150349987A1 (en) * 2014-05-29 2015-12-03 Qualcomm Incorporated Asynchronous multicarrier communications

Also Published As

Publication number Publication date Type
CA2480847A1 (en) 2003-11-06 application
EP2219315A1 (en) 2010-08-18 application
KR100934302B1 (en) 2009-12-29 grant
JP2006515119A (en) 2006-05-18 application
RU2004134568A (en) 2005-08-20 application
CA2480847C (en) 2012-07-10 grant
RU2339170C2 (en) 2008-11-20 grant
CN1666453A (en) 2005-09-07 application
US6847678B2 (en) 2005-01-25 grant
KR20040104616A (en) 2004-12-10 application
EP1497942A1 (en) 2005-01-19 application
WO2003092212A1 (en) 2003-11-06 application

Similar Documents

Publication Publication Date Title
Jafar et al. Adaptive multirate CDMA for uplink throughput maximization
Rohling et al. Performance comparison of different multiple access schemes for the downlink of an OFDM communication system
US6407993B1 (en) Flexible two-way telecommunication system
RU2233045C2 (en) Method and device for high-speed burst data transfer
US5737358A (en) Multiplexed radio communication system
US7016319B2 (en) Method and apparatus for reducing co-channel interference in a communication system
US7069009B2 (en) Apparatus and method for allocating resources of a virtual cell in an OFDM mobile communication system
Mahmoud et al. OFDM for cognitive radio: merits and challenges
US20070086474A1 (en) Method for estimating a map size in a wireless mobile communication system
EP0682423A2 (en) Code division multiple access system providing variable data rate access to a user
US20030123425A1 (en) Method and apparatus for controlling transmissions of a communications system
US20090201872A1 (en) Segment sensitive scheduling
US5619493A (en) Spread-spectrum, frequency-hopping radio telephone system with voice activation
US20040162097A1 (en) Peak-to-average power ratio management for multi-carrier modulation in wireless communication systems
US7577118B2 (en) System and method of classifying remote users according to link quality, and scheduling wireless transmission of information to the to the users based upon the classifications
US20090147748A1 (en) Transmission apparatus, reception apparatus, mobile communications system and transmission control method
US20020187799A1 (en) System and method for link adaptation in communication systems
US8315671B2 (en) Radio communication method and radio base transmission station
US7289494B2 (en) Systems and methods for wireless communication over a wide bandwidth channel using a plurality of sub-channels
US7257406B2 (en) Restrictive reuse set management
EP1594260A1 (en) Method for inter-cell interference coordination with power planning for OFDM mobile communication system
US20050157670A1 (en) Multiple user adaptive modulation scheme for MC-CDMA
US7548752B2 (en) Feedback to support restrictive reuse
US20070105508A1 (en) Wireless communication methods, systems, and signal structures
US20110021153A1 (en) Centralized cross-layer enhanced method and apparatus for interference mitigation in a wireless network

Legal Events

Date Code Title Description
AS Assignment

Owner name: RAYTHEON COMPANY, MASSACHUSETTS

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:BEREZDIVIN, ROBERTO;BREINIG, ROBERT J.;TOPP, ALLAN R.;AND OTHERS;REEL/FRAME:014008/0129;SIGNING DATES FROM 20030417 TO 20030421

AS Assignment

Owner name: RAYTHEON COMPANY, MASSACHUSETTS

Free format text: OTHER-CORRECTIVE ASSIGNMENT TO BE RECORDED AT REEL/FRAME;ASSIGNORS:BEREZDIVIN, ROBERTO (NMI);BREINIG, ROBERT J.;TOPP, ALLAN R.;AND OTHERS;REEL/FRAME:014999/0916;SIGNING DATES FROM 20031203 TO 20040216

CC Certificate of correction
FPAY Fee payment

Year of fee payment: 4

AS Assignment

Owner name: POWERWAVE COGNITION, INC., NEW HAMPSHIRE

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:RAYTHEON COMPANY;REEL/FRAME:022450/0397

Effective date: 20090217

FPAY Fee payment

Year of fee payment: 8

AS Assignment

Owner name: RAYTHEON COMPANY, MASSACHUSETTS

Free format text: COURT ORDER;ASSIGNOR:POWERWAVE COGNITION, INC.;REEL/FRAME:034041/0918

Effective date: 20140905

FPAY Fee payment

Year of fee payment: 12